Win95 FAQ Part 4 of 14: Hardware

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Nov 8, 1998, 3:00:00 AM11/8/98
Archive-name: windows/win95/faq/part04
Last-Modified: 1998/11/08
Posting-Frequency: Every two months

Subject: 4. Making your hardware work

* 4.1. Device Manager basics
* 4.2. Does Plug & Play work on systems without a Plug & Play
* 4.3. How do I make this card work...
+ 4.3.1. ...sound card
o Sound Blaster (tm), SB Pro, SB16, AWE32 (tm)
o Sound Blaster 16 Plug & Play
o Clone sound cards listed with Windows 95
o Clone sound cards that need DOS drivers to
o sound card NOT listed with Windows 95
+ 4.3.2. card
o card listed with Windows 95
o card NOT listed with Windows 95
o Using old ODI drivers with Win95
o Using old NDIS2 drivers with Win95
o Using some DMA network cards on machines
with more than 16 MB
+ 4.3.3. ...scanner card
+ 4.3.4. ...caching IDE or caching SCSI card
+ 4.3.5. More on setting DMA properties to make old cards
* 4.4. How do I make this drive work...
+ 4.4.1. ...CD-ROM drives
o Using DOS drivers (Avoid at all costs!)
+ 4.4.2. …Flash PC card or hardcard for a notebook
+ 4.4.3. ...tape drives
o SCSI tape drives
o Non-SCSI tape drives (Floppy, parport,
FC-20, whatever)
+ 4.4.4. ...removable drive
* 4.5. How do I make this input device work...
+ 4.5.1. ...un-listed mouse
o How can I use the middle mouse button on
Logitech (or similar) mice?
+ 4.5.2. tablet
+ 4.5.3. ...MIDI keyboard
* 4.6. How do I fix hardware conflicts?
* 4.7. How do I get a list of what card is using what IRQ? (or
+ 4.7.1. Help with devices that use IRQ 2 or IRQ 9
* 4.8. How do I tell Win95 about cards it doesn't have drivers
* 4.9. Using "Safe Mode" to fix hardware problems
* 4.10. Basic ISA Plug & Play theory (Don't bother if you don't
like details)
* 4.11. Basic PCI Plug & Play theory (Don't bother also)
* 4.12. Other PnP theory (SCSI, monitors, printers, PCMCIA, etc)
* 4.13. Top ten hardware mistakes


Subject: 4.1. Device Manager basics

Right-clicking on "My Computer" and selecting "Properties" brings up a
properties sheet for the whole computer, including all hardware. You
find the hardware info on the Device Manager tab.

Device Manager is Hardware Central on Win95. Because PC hardware is an
absolute pain to configure, Win95 tries to show you how your
hardware's set up here. To get the settings for a particular piece of
hardware, find it in the Device Manager and double-click on it. Hit
the "resources" tab to get the list of its settings. Normally you
can't modify settings for a particular device, but some drivers let
you make changes. Still other drivers will let you make changes that
take immediate effect when you hit "OK", without re-starting the

Not all devices show up here, however. Only hardware devices with
Win95 drivers will appear here. Devices with Win 3.1 drivers, pure
software devices (like video codecs or PC speaker sound drivers), and
DOS real mode drivers will not show up here. If you use such drivers,
Device Manager cannot avoid hardware conflicts. Get Win95 drivers for
your stuff, or dump your hardware in favor of devices with Win95
support. Save yourself the headaches. Or just check out How to
reserve resources if you just have to use the old stuff.

Also, "The Meteor" ( took some
time to write up a PC hardware FAQ that answers many more questions
than this page does.


Subject: 4.2. Does Plug & Play work on systems without a Plug & Play BIOS?

Yes it does, amazingly. Win95 will assume the role of PnP manager if
your system does not have a PnP BIOS.

This is actually advantageous, because BIOS authors haven't gotten the
idea down pat yet. Early Award BIOSes, for example, don't work with
SB16 PnP boards, or boards with Crystal's CS4232 sound chipset,
because these devices have multiple resource needs that these BIOSes
can't handle. Other bugs include locating PnP network boards on top of
Joystick ports.

Whose BIOS does work, then? If you have a board with Intel's Triton
chipset, visit Try to get a non-PnP BIOS for your
MB if you have troubles. Phoenix and Intel worked pretty close
together to straighten it out. AMI's pretty good with modern boards.
For Award, get a newer BIOS from your PC's manufacturer.


Subject: 4.3. How do I make this card work...

* 4.3.1. ...sound card

* Sound Blaster (TM), SB Pro, SB16, AWE32 (TM)

Simple. Plug it in and load Win95 drivers, or run Add New Hardware.
One thing Win95's really good at finding is original Creative Labs
hardware. To make DOS games run in DOS sessions, you might need to
change the card's settings to "traditional" settings: I/O port
220-22F, I/O port 388-38B, IRQ 5, DMA 1, DMA 5.

Win95 tends to allocate odd resources to SB16s. To avoid this, make
sure those resources are available, including freeing them in your
BIOS setup if you have such an option. A stock SB16's "Basic
Configuration 6" exposes all the SB16's on board hardware, including
both DMA channels, the OPL3 synth port, and the MIDI port.

* Sound Blaster 16 Plug & Play

Plug & Pray is more like it.

The PnP manager will have problems configuring this card if its
"preferred resources" aren't available. Try to free up the standard
I/O, Interrupt, and DMA values a Sound Blaster normally uses: A220,
I5, D1, H5 (DMA 5). If you use an Award BIOS be sure to set those
resources as "No/ICU" or otherwise available for use. You can
hand-edit the resource settings from Device Manager if necessary.

Non PnP systems will work with the SB16 PnP card, because Win95 will
allocate resources the card can actually use.

Whatever you do, do not install Creative's PnP Manager software on a
Win95 system. That DOS/Win 3.1 PnP Manager is for systems running good
ol' DOS. You will need the DOS PnP Manager for setting up Single
Mode DOS programs, where you specify a new DOS configuration for the
game, however. Try not to let the PnP manager installer add anything
to your Windows directory; you can specify this when you install the
PnP Manager by changing the Windows directory choice to "None".

NOTE: Creative's newest PnP sound cards come with a whole slew of
sound utilities that replicate many of Win95's built-in programs! This
is a waste of disk space. For example, you try to use Creative's CD
player, you insert an Audio CD, and Win95's CD Player auto-runs.

* Clone sound cards listed with Windows 95

Microsoft included quite a list of weird chipsets in Win95's sound
support, and most of the Windows Sound System clones offer Sound
Blaster emulation in DOS sessions! The list currently includes:
* Thunder Boards
* Media Vision (Pro Audio Spectrum)
* Windows Sound System (Analog Devices 1448 and Compaq (TM) Business
* ESS 688 and 488

* Clone sound cards that need DOS drivers to run

Only SB16 class cards actually need "DOS drivers" to operate, or at
least, they're the only ones that actually stay resident when you load
them. Other cards (Mozart class cards for example) will work with
Win95's SB Pro drivers, or Windows Sound System drivers

But if you have a card that won't work with SB drivers, or it
supposedly requires DOS drivers, here's what to do. I'll use Oak
Mozart class cards as an example, as this works perfectly with Mozart
1. Install the card software, and be sure NOT to install Windows
support for the card. Just to be sure, back up SYSTEM.INI before
installing the software.
2. Reboot the computer, but hit F8 on "Starting Windows 95..." and
select "Command Prompt Only". This runs through your normal DOS
startup without actually running Win95.
3. Type MEM /C, and compare this module listing with the files in the
CONFIG.SYS and AUTOEXEC.BAT that the sound software modified. Do
any of the resulting files remain resident? In the case of Mozart
class cards, they will not remain resident. If the sound software
modified SYSTEM.INI, restore it with the backup you made.
4. If no files remain resident, reboot and let Win95 run. Then
install drivers for the SB Pro, or Windows Sound System, depending
on what the card emulates. Re-boot and see if sound works.

Here's what's happening: The DOS "drivers" load and initialize the
sound card. Once this initialization is done, it will operate like a
regular SB or WSS card, and you can use Win95 drivers for SB or WSS.
This technique also works for CD-ROM support; if you let the sound
card "driver" initialize the card, then install Win95 support for
whatever CD-ROM card it emulates, it will work without having to load
DOS CD-ROM drivers for it.

DirectX and 4.00.950B users will want to use this capability, because
your sound card manufacturer might've not made DirectSound drivers for
that card yet. OPTi's 82C9xx cards for example, DO have Win95 drivers,
but don't support DirectSound yet. Using their SNDINIT program,
alongside a Sound Blaster Pro DirectSound driver, works around this
problem rather nicely.

* Sound card NOT listed with Windows 95

Cards not listed with Win95 will 90% work with Microsoft's SB Pro or
Windows Sound System drivers. WSS cards will even work with DOS games
in DOS sessions, if you enable Sound Blaster emulation. Still other
cards, like Crystal's CS4232, do SB emulation in hardware, at the same
time as WSS.

See the previous section on using initialization "drivers", which will
let you use Win95's SB Pro or WSS drivers with your unlisted sound

* 4.3.2. card?

Win95 introduces a new version of Network Device Interface Spec (NDIS)
3.1. NDIS 3.1 allows for PnP events, such as activating network
clients when you insert a PCMCIA card. Win95 comes with quite a
handful of NDIS 3.1 drivers for many cards, and I'll cover them first.
I also go into a whole mess of network stuff in another section.

* Net card listed with Windows 95

If a card is listed in Win95's built in driver list, it has an NDIS
3.1 driver. Most of the time, Add New Hardware will detect it and
install a driver for it. If not, you can manually add the driver from
the list. On occasion, Win95 will goof on its first resource choices,
but as it tells you, you can immediately run Device Manager to correct

Most of the supplied drivers include a DOS (NDIS 2) driver as well as
the NDIS 3.1 driver. This driver lets you run the card in Single Mode
DOS by typing net start redir or net start nwredir from a DOS prompt.

* Net card NOT listed with Windows 95

Of course, no hardware maker should be in the DOS box business these
days without Win95 drivers. Check with them first. Otherwise, Win95
will use NDIS 2.0 or ODI drivers if you're stuck. Both options sit

* Using old ODI drivers with Win95

Life stinks sometimes; too many card makers believe only Novell does
PC networks. Ahh well. Real mode ODI drivers will work with Win95
protected mode protocols and drivers, as Novell designed ODI to work
with NDIS protocols and clients.

You need three real mode TSRs to use a network card with an ODI

LSL.COM (Comes with the net card)
The net card driver itself (Referred to as an MLID)
ODIHLP.EXE (Comes with Win95)

You also need to install the "Existing ODI driver" using Add New
Hardware, or Network control panel. Adding the "Existing ODI Driver"
will install odihlp.exe, needed to link the real mode ODI drivers with
NDIS 3.1.

Finally, you need to write a net.cfg file for the ODI support. NDIS on
top of ODI only works with Ethernet and Token-Ring (If you know of
others please tell me!) ArcNet will not work in this configuration,
but Win95 comes with a generic ArcNet driver for NDIS 3.1. You also
need to specify all the frame types your adapter type can handle, for

link driver 3c5x9
frame ethernet_802.2
frame ethernet_802.3
frame ethernet_snap
frame ethernet_ii

Some NDIS protocols require the weird frame types. In particular,

Copy this net.cfg to the same directory where you keep and the
net card driver itself (Stick them in your Win95 directory for

* Using old NDIS2 drivers with Win95

Like ODI support, Win95 will use real mode NDIS 2.0 drivers as well,
but this eats significant amounts of conventional memory; even more
than ODI drivers use!

To use an NDIS 2.0 driver, you use Add New Hardware as before, and
tell it where to find the NDIS 2 driver. You can configure the card
like any other NDIS 3.1 card, but Win95 will add this line to

net start

This will load the DOS protocol manager and the xxxxx.dos net card
driver into conventional memory. When loads, it will load the
NDIS 2 protected mode helper and start the network. NDIS 2 driver info
will appear in The Registry, and should also appear in protocol.ini
for compatibility. You can hand-edit protocol.ini as you normally
would for NDIS 2 drivers, and Win95 will apply these changes the next
time it re-starts.

Some NDIS 2 drivers exist in \drivers\netcard on the Win95 CD-ROM, so
check there if you don't see your card listed. Also check out
Microsoft's Win95 driver library.

* Using some DMA net cards on machines with more than 16 MB

Some token-ring cards and maybe a few Ethernet cards need to use an
ISA DMA channel to off-load CPU time. If your computer has more than
16 MB memory, it can hang the computer, because Win95 will attempt to
DMA into memory that the net card can't reach. ISA slots only have 24
address lines (to access 16 MB).

To make these cards work, run Device Manager and find the "Direct
Memory Access Controller" driver in System Devices. In its settings,
turn on "Allow DMA into first 16 MB only".

This switch will also work for other DMA devices in case the driver
doesn't already account for this.

* 4.3.3. ...scanner card?

If you own an HP scanner you're in luck; HP designed Win95 versions of
their TWAIN scanner interface software. Download it from HP's TWAIN currently depends on Advanced SCSI
Programming Interface, so you need a Win95 driver for your SCSI host
adapter to use it. Non-SCSI scanners can work with the Win 3.1
software provided for it, but try to avoid loading real mode scanner
drivers just to make your cheap hand scanner work. Don't waste your
time. It may be possible to find a Win95 TWAIN driver for your
non-SCSI scanner; ask the manufacturer.

Check out Epson's home page ( for Win95
versions of TWAIN for their Action Scanner and ES series scanners.
These support their SCSI and Parallel Port scanners. Again you'll need
a Win95 driver for your SCSI card, as Epson's TWAIN requires ASPI as

4.00.950B users can take advantage of the Imaging components that come
with it. These components include "thunk" layers between 16-bit
scanners and 32-bit apps, and a simple image editor that uses your

* 4.3.4. ...caching IDE or caching SCSI card?

Promise Technology ( has
Win95 versions of its Caching IDE host adapter drivers, so be sure to
grab them. Tekram ( will also have
drivers for its IDE caching adapter, but the SCSI caching adapter
should work with Adaptec 1540 drivers if they didn't get around to
writing Win95 SCSI drivers yet.

Most of the time, the standard IDE drivers will work with caching IDE
cards, though they won't take advantage of the card's cache. If you do
manage to get a Win95 caching IDE driver, try to set Win95's own cache
to bare minimum (384 KB) so you make good use of your controller's
cache instead. Edit your system.ini's [vcache] section:


Then it will almost solely rely on the controller's cache and free up
valuable memory for your programs.

* 4.3.5. More on setting DMA properties to make old cards work

While Win95 will honor settings you make in system.ini for things like
DMABufferSize, I tend to prefer keeping system.ini clean to ease

In Device Manager, find the "Direct Memory Access Controller" in
System Devices. Here you may specify the DMA buffer size and wether or
not Win95 will allow DMA above the 16 MB memory area. This switch is
for hardware that uses ISA DMA to directly access memory, but prevents
the device from trying to DMA into memory above 16 MB (the limit of
the 24 address lines on the ISA bus). This switch will not affect VESA
or PCI Bus Master devices, as they don't require ISA DMA channels.

NOTE: A Win95 driver for an ISA DMA device should be smart enough not
to try to DMA into memory above 16 MB by design. For example, SCSI
drivers written by Adaptec and sound card drivers will allocate
buffers below 16 MB regardless of how you set these switches. As a
result you shouldn't have to mess with them.


Subject: 4.4. How do I make this drive work...

* 4.4.1. CD-ROM drives

I know of three classes of CD-ROM devices in Win95:

IDE: These work off standard IDE adapters if you have Win95 drivers
for the IDE cards. Just plug and play, like you're supposed to. No
fancy CD-ROM controller drivers. And yes, you CAN use an IDE CD-ROM
and hard drive on the same cable, and still get 32-bit access on both
devices. The IDE miniport driver takes care of the gory details.
CD-ROM drives alone on a secondary adapter must be a Master drive;
ATAPI spec demands there be a Master device on each IDE adapter to
work properly. Grab Microsoft's IOS.VXD Update
( if you're having
trouble playing videos etc off an IDE CD-ROM.

SCSI: Win95 works best with SCSI-II CD-ROM drives, regardless of your
host adapter type. Just get Win95 drivers for the SCSI card and let
ASPI find it. CD-ROM Jukeboxes even work quite well, though some
SCSI-I jukeboxes will have troubles. Otherwise, PnP works well here,
too. SCSI is the way to go for many such devices in the same computer.
There's an update for some CD-ROM Jukeboxes
( available if
you have troubles.

Proprietary: These include the Mitsumi, Sony CDU-3xx, Matsushita
(Panasonic/AT) interfaces. These require a CD-ROM miniport driver
specially designed for the card and the drive combination you have!
For example: You can't use a TEAC CD-ROM with a SB Pro CD-ROM card
driver; you have to use a TEAC driver designed for the SB Pro card and
TEAC drive. Proprietary interfaces include those built into sound
cards; most of the time they emulate one of these three proprietary
CD-ROM cards, and you can use a Win95 driver.

* Using DOS CD-ROM drivers (Avoid at all costs!)

You only need to use a DOS CD-ROM driver if you exit Win95. This
includes the "Restart Computer in DOS mode" option, where you can't
play a game in a DOS session under Win95. Look here in FAQ page 12
for details on how to do this properly.

If you find you need a DOS CD-ROM driver to use the drive in Win95,
then the drive's broken. See the dealer or manufacturer to get it
fixed or get a Win95 driver for it. I find that real mode CD-ROM
drivers in Win95 are very unreliable.

* 4.4.2. ...Flash PC card or hardcard for a notebook computer?

To make the Flash card work, just insert it! Provided you installed
Win95 drivers for your notebook's PC card slots, it will mount it and
assign a drive letter to it.

To make Win95 support PC cards in protected mode, run the PC Card
control panel. The first time you run this, it offers to install
32-bit support. Let it do so! It will also remove any real mode and
Win 3.1 drivers it recognizes, but for weird PC card software you
might need to do some trimming afterwards. Just hide or delete your
DOS startup files, and trim off any unusual entries in system.ini.

File system notes: PC card users told be about some third-party Flash
file systems that require DOS PC card drivers to use. I'd just say,
don't waste your time with these non-standard file systems and use
good ol' FAT.

* 4.4.3. tape drives

Microsoft's backup program only works with cheap tape devices, like
the floppy port and parallel port tape drives. If you have one of
these then just use the built in backup program. For other kinds of
drives, see below.

* SCSI tape drives

Colorado Memory Systems, who wrote the MS Backup for Win95, was kind
enough to release a version that works with more tape devices.
Download Colorado Backup and install it, for a Win95 tape drive
subsystem that supports SCSI tape drives. Get excellent speed and
reliability with this software and SCSI tape drives.

Adaptec includes tape backup software with EZ-SCSI 4.0. It is a
veritable clone of HP's Colorado Backup for Win95.

* Non-SCSI tape drives (Floppy, parport, FC-20, whatever)

If you own a Colorado non-SCSI tape drive, Download Colorado Backup
1.51. Version 1.51 also handles TRAVAN parallel port drives and floppy
based drives attached to an FC-10 or FC-20 controller card.
Non-Colorado customers should ask their manufacturer for Win95
versions of their software. For example: Arcada
( supports Conner floppy-based tape
drives. The reason behind this is Colorado's tape drivers will FIND
non-Colorado drives, but the backup program will blatantly ignore
them. Ahh... what do you want for free?

Conner also has a basic Win 3.1 version of Backup EXEC patched to
support Win95 long filenames and Registry back-ups; check with your
tape drive dealer for a free update.

Microsoft's built in back-up program works with old cheap QIC-40 and
QIC-80 class devices attached to a floppy port or parallel port, and
you won't really get a performance boost with third-party software
here anyway.

* 4.4.4. ...removable drive?

SCSI is your best, and in some cases, your only choice for removable

Just get a good Win95 compatible SCSI adapter and you can pick &
choose between many optical, SyQuest, floptical, whatever... drives.
The SCSI driver will find and mount any such devices it finds, though
some disks require partitioning. You can't partition removable disks
using FDISK, but Adaptec released their EZ-SCSI software for
Win95, which includes a removable disk partitioner. EZ-SCSI 4.0 will
work on pretty much any SCSI adapter, because Win95 has ASPI support
built in. Non-Adaptec owners can buy it. Adaptec's WFDISK (Windows
disk partitioner) for Win 3.1 will work too, as it uses ASPI.


Subject: 4.5. How do I make this input device work...

* 4.5.1. ...unlisted mouse?

Use the Standard mouse driver. Win95 has three standard drivers for
three different mouse ports; serial, PS/2, and Bus. The Bus Mouse
driver will work with mice plugged into an ATI Graphics Ultra card.

Since no one designs mice for something other than these three
connectors, you're probably better off getting a replacement mouse if
it doesn't work with Win95. For $10.00 you can find a good serial

* How can I use the middle mouse button on Logitech (or
similar) mice?

Win95 supports the third button as long as the mouse driver does. Use
Logitech's latest mouse driver (7.1) for Win95 to enable third mouse
button support. However, the applications need to LOOK for it.
Currently, the only Win95 app that uses the middle button is DOOM95 by
id Software.

* 4.5.2. tablet?

Both SummaGraphics
( and CalComp
( have Win95 versions of the WINTAB
interface, for their tablets. For other tablets you should see about
switching them to emulate a Summa or CalComp tablet, or check with
your manufacturer. As more pointing device makers write Windows NT
support, Win95 support will increase.

Many tablets work alongside of mice; when you move the mouse, motion
is relative, and when you move the tablet motion is absolute,
depending on the range of tablet you calibrated your screen to.

* 4.5.3. ...MIDI keyboard?

Load a Win95 driver for your MIDI interface, and use the same Win 3.1
software you used before, to record your MIDI keystrokes and other
events. Win95's Sound Blaster drivers support MIDI through the
joystick port, and MPU 401 compatible cards will work with the MPU 401
driver. Microsoft also included an MT-32 driver.


Subject: 4.6. How do I fix hardware conflicts?

Device Manager is your best tool for resolving conflicts. To run
Device Manager, right-click on "My computer" and hit "Properties",
then hit the Device Manager tab. Any device that failed to start will
have a (!) identifier with it, indicating some kind of failure.
Bringing up properties for that device will go into the details.

If your card causes a hardware conflict, you can adjust its settings
with the Resources tab. If your card uses jumpers, you will need to
power off the computer and adjust them, before the device will work.
If it is a software configurable device, adjusting the resources may
allow the device to start up without having to re-start the computer.
Sound cards often react like this.

You might have a resource conflict with a real-mode driver, or a Win
3.1 driver. These you can't resolve using Device Manager, but you can
tell Device Manager to reserve resources for such devices.
Double-click on "Computer" in Device Manager, and you can view all
resources in use, or reserve resources for non-Win95 drivers.
Reserving memory resources this way works like EMMExclude= lines in

* 4.7.1. Help with devices that use IRQ 2 or IRQ 9

Quick background... The first PC compatibles (XTs and 8088s) made
interrupt lines 2 to 7 available for ISA cards. IRQ 2 was marked as
"reserved" but was still available for developers. This was handy to
have because if you had a floppy drive (IRQ 6), two serial ports (IRQs
3 and 4), and two printer ports (IRQs 5 and 7), you were kinda stuck
with IRQ 2. MIDI devices are the most common devices that used IRQ 2.

ATs and better added a second interrupt controller (The interrupt
controller you see in Device Manager is really two interrupt
controllers cascaded) and the second controller used IRQ 2 to indicate
an interrupt occured on a line from IRQs 8 to 15. (Remember that IBM
"reserved" IRQ 2? Now you know why.) To maintain compatibilty with
devices that used IRQ 2, ATs wired IRQ 9 in place of IRQ 2 on the bus.
Whenever you install an 8-bit card that allows you to use IRQ 2,
you're really using IRQ 9. This wasn't enough because those MIDI
programs wouldn't understand what IRQ 9 was. Every incarnation of DOS,
from 2.0 up to 6.22, would cascade IRQ 9 events to the IRQ 2 handler
so these old programs would work. Guess what? Win95 no longer does

To use devices that allow IRQ 2, set that driver's setting to use IRQ
9 instead. The MPU-401 MIDI driver defaults to using IRQ 9, for
example. If you add an 8-bit internal modem to a system that has two
serial ports and a sound card, you should use IRQ 9 to avoid conflicts
with the other ports. "Basic Configuratrion 5" for a serial port lets
you select IRQ 9. Don't even try to use DOS software that attempts to
use "IRQ 2" because it simply won't work.


Subject: 4.7. How do I get a list of what card is using what IRQ? (or whatever)

Bring up Device Manager and double-click on "Computer". This will let
you view IRQs and other resources in use by Win95 drivers. You can
also hit Print... on the Device Manager sheet, which will print a
whole "MSD" style report of hardware resources in use.


Subject: 4.8. How do I tell Win95 about cards it doesn't have drivers for?

Bring up Device Manager and double-click on "Computer". Hit the
"Reserve Resources" tab, and tell it which IRQs, DMA channels, etc are
in use by non-Win95 drivers. Reserving memory like this works just
like excluding addresses in EMM386, or using EMMExclude= in

You MUST do this if you use real mode drivers or Win 3.1 drivers that
Win95 can't recognize, otherwise when you install a PnP device it may
try to allocate the used resources to the new device!


Subject: 4.9. Using "Safe Mode" to fix hardware problems

Safe Mode is a debugging mode which allows you to fix problems without
loading the offending drivers. You should not have to run Safe Mode
for any other purpose, in fact you can't run any big applications,
except Device Manager, while in there. ScanDisk works in Safe Mode,
but it takes much longer to perform disk checks.

To start your computer in Safe Mode, hit F8 on "Starting Windows
95...", then select Safe Mode from the choices. This option
automatically comes up if you interrupt Win95's boot up process, or it
freezes up or otherwise fails to start.

Also, while in Safe Mode, Device Manager cannot tell you about
resource conflicts, because the drivers didn't load. You might also
notice drivers for hardware you don't have; they will appear if there
were remnant Registry entries for them. These driver-remnants are good
candidates for removal!


Subject: 4.10. Basic ISA Plug & Play theory (Don't bother if you don't like details)

A PnP BIOS keeps a record of resources in use through a Non-Volatile
RAM (NVRAM), usually part of its Flash BIOS EEPROM. When you add a
device, Win95 tells the BIOS to add the resources in use to this list.
A BIOS must have these calls available to Win95 or it will never know
about what the OS added or reserved. The NVRAM is not the same as CMOS
RAM, which makes me wonder why they don't just replace the CMOS with
NVRAM for storing other settings, like lost hard drive parameters.

Also, when you install a PnP device, the BIOS polls it for the
resources it requires. The PnP device will have "Preferred",
"Acceptable", and "Marginal" operating resource requirements. The BIOS
will assign resources based on what the device can use, and record the
resources used in its NVRAM. Win95 can ask the BIOS what resources are
in use, and it can ask the BIOS if any new devices exist, which is
when you get the "Windows has found new hardware..." message. On a
Non-PnP system, Win95 handles all PnP requests by itself and stores
config info in the Registry.

Buggy BIOSes might not handle cards with multiple devices on it. If
you think you have a buggy BIOS, see about disabling its PnP features
and let Win95 take over as PnP manager. In this condition, Win95
stores all resources in use in its Registry and polls PnP cards by


Subject: 4.11. Basic PCI Plug & Play theory (Don't bother also)

PCI was Plug & play by design. A PCI BIOS will assign resources, but
the PCI cards don't care what resources they get. Often, the PCI cards
end up in unusual I/O spaces (like above the 3FF range of the original

Some PCI cards have hard-wired resource requirements (like video
cards), but the newest video cards are beginning to wean off that
requirement, as games stop depending on VGA and use DirectDraw under
Win95. Cases include the on-board video that some SIS motherboard
chipsets provide.

As per ISA PnP, The BIOS keeps its PCI config info in its NVRAM, and
Win95 keeps a copy in the Registry.


Subject: 4.12. Other PnP theory (SCSI, monitors, printers, PCMCIA, etc)

SCSI: Supposedly you can power-on a SCSI device while you computer is
running, and Win95 will enumerate and mount it instantly! OK, not
entirely. Sometimes it takes a few presses "Refresh" in Device Manager
before the new device appears, but it should work. The newest SCSI
peripherals can auto-configure themselves, where the host adapter
assigns them a SCSI ID. Normally, Win95 ASPI will scan the SCSI bus on
power-up and present you with the "Found new hardware" requester.

NOTE: A handful of SCSI drivers for Win95 seem to be missing Logical
Unit Number (LUN) support. LUN support lets things like CD-ROM
Jukeboxes work, by assigning a drive letter to each LUN. The result
is: You will only see ONE device and not six or seven. To fix this,
get an updated Win95 driver for your SCSI card, or get a different
card (All Adaptec drivers for AHA-1510 and up have LUN support; others
you might be able to turn on LUN support in their "Settings" tab in
the Device Properties.) Also check out MS's CD-ROM Changer Driver

Monitors: Win95 video drivers can poll the monitor for scan rate
information, if the monitor can reply back.

Printers: PnP printers are just starting to show up. This is where the
printer sends back info about itself on a bi-directional parallel
port. The "Windows has found new hardware..." requester will show up,
asking you for a Win95 printer driver, and you can begin using the
printer right away.

PCMCIA: If you have a notebook computer, you need Win95. Forget that
messy DOS PC card driver nonsense and incompatibilities with certain
PC card chipsets, and special "no card services" drivers. Win95 runs
Card Services in protected mode, using no conventional memory, and
will give you the "Found new hardware" requester when you insert a new
card for the first time. Modems work straight away with Win95 TAPI
programs. Net cards will re-connect to the network for you when you
insert them. SCSI cards will mount all devices on its cable. And best
of all: You can still use dumb DOS programs that require EMS memory at
the same time!


Subject: 4.13. Top ten hardware mistakes

10. Using a DOS CD-ROM driver

9. Using real mode PCMCIA drivers (DOS PCMCIA sucks!)

8. Using a Gravis Ultrasound with Win 3.1 drivers (Visit Gravis,
( GUS owners, and get your fair support!)

7. Running a Win 3.1 setup program to install drivers

6. Running a DOS setup program to install Win 3.1 drivers

5. Installing a Plug & Play modem without enabling Plug & Play on the

4. Buying a piece of hardware without Win95 support

3. Buying a whole bunch of HDs, CD-ROM, tape drive, scanner, without
considering SCSI

2. Buying a notebook computer without Win95

1. Buying an IBM compatible with an Award PnP BIOS (Upgrade to MR
BIOS ( soon!)

= I am Gordon of Winterpeg. Junk mail is futile. Post MakeMoneyFast =
= Find out why: Or eat pink meat from a can =
= World's best computer: they're both the same =
= Windows 95 FAQ: =

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