Irq weirdness
Robert Jones
in fact I thought I knew hardware real well being that I have had them since
286 days
recently I bought a new hdd for my older p3 750
installed it
formatted it
installed XP
noticed battlefield 1942 bogged now
looked at stuff and found this
Usb hubs 1 and 2 are on irq 9
Ati 8500 le is on irq 9
nic is on irq 9
scsi Adaptec 2940 is on Irq 9
sound blaster live 5.1 oem is on irq 9
so I disabled com , printer , Usb pulled the scsi card out and now I have
unused irq's but still video remains on 9
note : shut off plug an play OS setting in bios post screen said video was
on irq 11 but as windows booted it changed back to 9
moved the nic card to another slot didn't change irq...(very odd behaviour
all other pc's I've worked on this is a sure way to get it to move)
changed nic card now has Intel nic card still went to 9
removed sound blaster 5.1 installed awe 64 gold manually set it to irq 5....
for some reason it went to 10 when I installed nothing else is on 5
but I cant force the video or nic to another irq ..... is there any way I
can alter this ... settings in XP are greyed out in resource settings for
the hardware
as you can see I have tried all oh yes one or two more things
old hdd had win 98 se on it and I when I boot to it irq's are all perfect
and I have had win XP on this before ... it was dual boot and irq settings
would never change from one OS to the other.
relic
IRQ sharing works pretty good in XP with fully ACPI Compliant hardware, but XP
is sensitive to Sound Cards and NICs sharing IRQs. Check your motherboard
manual to see which slots you can put them in where they won't share IRQs with
any other card or active on-board device. Note that some mbs (MSI) tend to
have the USB IRQs follow card movement (they should fix it). You may get away
with USB devices sharing IRQs with something in that case.
Yes, Plug and Play OS in BIOS should be OFF for XP.
--
- relic -
http://relic-2.notlong.com
If you think there is good in everybody, you haven't met everybody.
GeoW
relic wrote:
> Robert Jones wrote:
>> ok .. I'm not new to pc's
>> in fact I thought I knew hardware real well being that I have had
>> them since 286 days
>> recently I bought a new hdd for my older p3 750
>> installed it
>> formatted it
>> installed XP
>> noticed battlefield 1942 bogged now
>> looked at stuff and found this
>> Usb hubs 1 and 2 are on irq 9
>> Ati 8500 le is on irq 9
>> nic is on irq 9
>> scsi Adaptec 2940 is on Irq 9
>> sound blaster live 5.1 oem is on irq 9
<snip>
>
> IRQ sharing works pretty good in XP with fully ACPI Compliant
> hardware, but XP is sensitive to Sound Cards and NICs sharing IRQs.
> Check your motherboard manual to see which slots you can put them in
> where they won't share IRQs with any other card or active on-board
> device. Note that some mbs (MSI) tend to have the USB IRQs follow
> card movement (they should fix it). You may get away with USB
> devices sharing IRQs with something in that case.
>
>
> Yes, Plug and Play OS in BIOS should be OFF for XP.
Just to elaborate on relic's answer, You have to think of irq's from two
angles. One being the hardware angle, and the other being the software
angle. Most motherboards only have 4 irq's addressable, so in some cases, 2
card slots will share a hardware IRQ. Some cards, like Video, Sound, and
NIC's can share an IRQ in software, but will have problems if they are
sharing hardware irq's. The moving of cards in slots can fix this basic
problem, and then the os can assign them the same software IRQ without
problems in an ACPI system.
relic
One more thing. If you aren't using COM1, COM2, LPT1, or LPT2, disabling them
in BIOS will free up more IRQs for use by XP's ACPI implementation.
Robert Jones
around and it still wanted irq 9
I changed the driver for the computer tab in the device manager from acpi to
standard pc to see what would happen and my irq's were ok then but now I
have to manually shut off the power supply now to shut down the pc (like the
old AT boards)
"relic" <repl...@newsgroup.com> wrote in message
news:gmu_a.33868$8N.14...@twister.socal.rr.com...
GeoW
relic wrote:
> GeoW wrote:
>>
>> Just to elaborate on relic's answer, You have to think of irq's from
>> two angles. One being the hardware angle, and the other being the
>> software angle. Most motherboards only have 4 irq's addressable, so
>> in some cases, 2 card slots will share a hardware IRQ. Some cards,
>> like Video, Sound, and NIC's can share an IRQ in software, but will
>> have problems if they are sharing hardware irq's. The moving of cards
>> in slots can fix this basic problem, and then the os can assign them
>> the same software IRQ without problems in an ACPI system.
>
> One more thing. If you aren't using COM1, COM2, LPT1, or LPT2,
> disabling them in BIOS will free up more IRQs for use by XP's ACPI
> implementation.
Good call, actually another thing you can do is assign both COM ports to the
same IRQ (and different address) in BIOS as well. I had to do that to free
up an internal modem irq slot
GeoW
Robert Jones wrote:
> pls reread original post... I know slots are shared.... I moved the
> nic around and it still wanted irq 9
> I changed the driver for the computer tab in the device manager from
> acpi to standard pc to see what would happen and my irq's were ok
> then but now I have to manually shut off the power supply now to shut
> down the pc (like the old AT boards)
>
You have to also go to the ADD HARDWARE section of the control panel and
install "NT APM/Legacy Support" drivers.
relic
> pls reread original post... I know slots are shared.... I moved the
> nic around and it still wanted irq 9
> I changed the driver for the computer tab in the device manager from
> acpi to standard pc to see what would happen and my irq's were ok
> then but now I have to manually shut off the power supply now to shut
> down the pc (like the old AT boards)
>
The original post is too long to read. This is better.
If you installed the "Standard PC" install APM Legacy Support in Add/Remove
Programs then go to the APM tab in Power Options and turn it on.