PC Monitors for SGI Indigo2?
Robert J. Dennison
finding a reasonably price monitor to use with it.
Assuming the monitor doesn't have a 13W3 connector and I need to
purchase an adapter, what are the specs I need to look for in a PC
monitor? (scan rates, sog, etc.)
Thanks,
R.
Michael Laajanen
Usually the possible highest frequency(or resolution) is the number to
look for.
Assume that you run at 1280x1024 pixel resolution and have update
frequency of 75 Hz, then you have ~1280x1024x75 = 98MHz so a monitor
having a sweep frequency of > 100MHz should be fine, or just look for a
monitor that can do 1280x1024 at 75Hz.
Regarding Sync-On-Green, I can't say if that is a must requirement, I
don't think so.
Anyhow, if you look on EBAY you will find alot of these 13W3/DSUB-15
converters, they are used on SUNs aswell.
/michael
Tony 'Nicoya' Mantler
Michael Laajanen <michael.laajanen.no-spam.@telia.com> wrote:
: HI,
Your advice is well meaning but somewhat misguided.
The limit in CRT monitors is the horizontal retrace rate. This rate is (roughly)
refresh * lines, which for 1280x1024@75 would be approximately 77KHz.
The limit for your video card is the pixel rate, which you can esimate by
refresh * lines * columns * 4/3 (the extra is to account for the horizontal
retrace sequence). This is approximately 131MHz for 1280x1024@75.
The Indigo2 should put out both a sync signal on RGB, as well as an external
sync signal on one or more of the auxiliary 13w3 pins. You should ignore all
this and just buy a good Sony CRT. Both of my Sonys (old 17seIIt and new G520)
work perfectly with unmodified SUN-style 13w3 adapters, which is about the most
hostile setup you can get.
Please note that the pinout for the SGI 13w3 adapter differs from that used with
Sun machines (the main 3 colours are the same, but the 10 aux pins are
different). You will not damage the system, but it may not work with lesser
monitors.
Cheers - Tony 'Nicoya' Mantler :)
--
Tony 'Nicoya' Mantler -- Master of Code-fu -- nic...@ubb.ca
-- http://nicoya.feline.pp.se/ -- http://www.ubb.ca/ --
Michael Laajanen
Tony 'Nicoya' Mantler wrote:
> In article <Ix9ac.54623$mU6.2...@newsb.telia.net>,
> Michael Laajanen <michael.laajanen.no-spam.@telia.com> wrote:
>
> : HI,
>
> Your advice is well meaning but somewhat misguided.
hehe, ofcourse it's well ment I just (tried mybe failed) to made a easy
to understand simpified calculation, usually if you get the correct Hor
rate in this case in the region > 100MHz the hor-retrace period will
follow!
BTW, old Sun displays(sony) something like before 1995 they did not work
at that high rate so they used 1152x9xx something.
On big problem in the beginning was the D/A converters at that high freq.
>
> The limit in CRT monitors is the horizontal retrace rate. This rate is (roughly)
> refresh * lines, which for 1280x1024@75 would be approximately 77KHz.
>
> The limit for your video card is the pixel rate, which you can esimate by
> refresh * lines * columns * 4/3 (the extra is to account for the horizontal
> retrace sequence). This is approximately 131MHz for 1280x1024@75.
>
>
> The Indigo2 should put out both a sync signal on RGB, as well as an external
> sync signal on one or more of the auxiliary 13w3 pins.
Indigo should send out both H/V on the 13W3 otherwise it will not work,
and then it could send out composite sync on green but that is not used
any more i guess, right?
> You should ignore all
> this and just buy a good Sony CRT. Both of my Sonys (old 17seIIt and new G520)
> work perfectly with unmodified SUN-style 13w3 adapters, which is about the most
> hostile setup you can get.
Any monitor will work that fits the freq up, Sony is just the one they
use for stationary work, you seldom use them for professional work or in
mobil environment due to the weakness of the design.
>
> Please note that the pinout for the SGI 13w3 adapter differs from that used with
> Sun machines (the main 3 colours are the same, but the 10 aux pins are
> different). You will not damage the system, but it may not work with lesser
> monitors.
>
The difference is from what understand the meaning/use of ID signals to
inform the Graphic adapter what kind of monitor, RGB and V/H sync are on
the same pins or?
cheers
michael
Tony 'Nicoya' Mantler
Michael Laajanen <michael.laajanen.no-spam.@telia.com> wrote:
: hehe, ofcourse it's well ment I just (tried mybe failed) to made a easy
: to understand simpified calculation, usually if you get the correct Hor
: rate in this case in the region > 100MHz the hor-retrace period will
: follow!
I have never seen a monitor with a horizontal retrace rate anywhere near 100MHz,
and I doubt I will any time soon. You are very confused.
: BTW, old Sun displays(sony) something like before 1995 they did not work
: at that high rate so they used 1152x9xx something.
:
: On big problem in the beginning was the D/A converters at that high freq.
The D/A converters are in the video card, not the monitor.
: Indigo should send out both H/V on the 13W3 otherwise it will not work,
: and then it could send out composite sync on green but that is not used
: any more i guess, right?
SGI's primary sync type is SOG. You are not guaranteed to find the other sync
varieties on any or all SGIs, though they are present on some.
: Any monitor will work that fits the freq up, Sony is just the one they
: use for stationary work, you seldom use them for professional work or in
: mobil environment due to the weakness of the design.
*IF* you have a proper SGI-type 13w3 adapter, the monitor must be able to
tolerate sync signals on the R, G and B pins. Not all monitors tolerate this.
*IF* you don't have a SGI-type 13w3 adapter, and instead use a Sun-type, your
monitor must both be able to sync to an SOG signal, and ignore the gibberish
that ends up on the regular sync pins. Not all monitors tolerate this.
*IF* you use a non-SGI type 13w3 adapter and your monitor does do SOG but does
not tolerate gibberish on the sync pins (usually the monitor will switch into
power-saving mode, despite being SOG compatible) you can clip off the 10 smaller
pins of the 13w3 adapter and usually get a working setup.
A good Sony monitor is the only brand I've seen that will handle all these
situations automatically without complaining.
I don't understand what you're trying to say about "weakness of design". I
suspect you are trolling, and will not respond to your unfounded allegations.
: The difference is from what understand the meaning/use of ID signals to
: inform the Graphic adapter what kind of monitor, RGB and V/H sync are on
: the same pins or?
The R, G and B signals are on the same pins, but all the other pins are wired
differently. This results in sync signals ending up on random ID pins, and vice
versa. Many monitors do not tolerate this and will refuse to operate properly.
Michael Laajanen
Tony 'Nicoya' Mantler wrote:
> In article <F_aac.54627$mU6.2...@newsb.telia.net>,
> Michael Laajanen <michael.laajanen.no-spam.@telia.com> wrote:
>
> : hehe, ofcourse it's well ment I just (tried mybe failed) to made a easy
> : to understand simpified calculation, usually if you get the correct Hor
> : rate in this case in the region > 100MHz the hor-retrace period will
> : follow!
>
> I have never seen a monitor with a horizontal retrace rate anywhere near 100MHz,
> and I doubt I will any time soon. You are very confused.
Yes I am writing strange, sorry it should be pix freq is higher then the
"77KHz" will be higher to, sorry for that (:
So if one "value" is higher the other is higher to, simple speaking :)
>
>
> : BTW, old Sun displays(sony) something like before 1995 they did not work
> : at that high rate so they used 1152x9xx something.
> :
> : On big problem in the beginning was the D/A converters at that high freq.
>
> The D/A converters are in the video card, not the monitor.
Yes, I just guessed why Sun did limit the resolution to 1152x900 and ~80MHz.
>
>
> : Indigo should send out both H/V on the 13W3 otherwise it will not work,
> : and then it could send out composite sync on green but that is not used
> : any more i guess, right?
>
> SGI's primary sync type is SOG. You are not guaranteed to find the other sync
> varieties on any or all SGIs, though they are present on some.
OK, that is important.
>
>
> : Any monitor will work that fits the freq up, Sony is just the one they
> : use for stationary work, you seldom use them for professional work or in
> : mobil environment due to the weakness of the design.
>
> *IF* you have a proper SGI-type 13w3 adapter, the monitor must be able to
> tolerate sync signals on the R, G and B pins. Not all monitors tolerate this.
>
Do you meen that they send sync on all three, which one will the monitor
pick then, and why are you sometimes talking about SOG?
> *IF* you don't have a SGI-type 13w3 adapter, and instead use a Sun-type, your
> monitor must both be able to sync to an SOG signal, and ignore the gibberish
> that ends up on the regular sync pins. Not all monitors tolerate this.
What means gibberish? I guess that you mean that the monitor must first
look for SOG and if found skip H/V sync?
>
> *IF* you use a non-SGI type 13w3 adapter and your monitor does do SOG but does
> not tolerate gibberish on the sync pins (usually the monitor will switch into
> power-saving mode, despite being SOG compatible) you can clip off the 10 smaller
> pins of the 13w3 adapter and usually get a working setup.
>
> A good Sony monitor is the only brand I've seen that will handle all these
> situations automatically without complaining.
The PRO monitors from Misubishi, Conrac, Barco, Hitachi and more should
work fine to.
>
> I don't understand what you're trying to say about "weakness of design". I
> suspect you are trolling, and will not respond to your unfounded allegations.
>
>
Sorry for my English "Trolling" means nonsense/imaging or?
Back to subject, what I mean is that you can't use a trinitron monitor
in a non stable environment due to shaking and so which the trinitrons
mask can handle(use you hand on top of your Sony and you see what IU
mean), thats what I mean with mobile.
Anyhow, good to know that the ID pins and H/V sync can be on different
pins so I don't break the adapter when I have my first SGI soon I hope... :)
cheers
Michael
Tony 'Nicoya' Mantler
Michael Laajanen <michael.laajanen.no-spam.@telia.com> wrote:
[...]
: > *IF* you have a proper SGI-type 13w3 adapter, the monitor must be able to
: > tolerate sync signals on the R, G and B pins. Not all monitors tolerate
: > this.
: >
: Do you meen that they send sync on all three, which one will the monitor
: pick then, and why are you sometimes talking about SOG?
On the Indigo2, yes. I don't know why they output it on all 3 lines, but they do.
: What means gibberish? I guess that you mean that the monitor must first
: look for SOG and if found skip H/V sync?
Some monitors will see "sync pin pulled low/high" and interpret this as "go into
powersaving mode", regardless of there being an active signal and sync being
delivered on the RGB lines.
: > A good Sony monitor is the only brand I've seen that will handle all these
: > situations automatically without complaining.
: The PRO monitors from Misubishi, Conrac, Barco, Hitachi and more should
: work fine to.
I haven't tested those monitors, so I can't guarantee they will work. They
should, they might, but I can't say "they will". I *have* tested Sony monitors,
and they do work, so if someone asks me "what monitor do I get" I'll tell them
to go get a Sony.
Unfortunately you can't look up this type of compatability information in a spec
sheet or get it out of a sales rep.
: Back to subject, what I mean is that you can't use a trinitron monitor
: in a non stable environment due to shaking and so which the trinitrons
: mask can handle(use you hand on top of your Sony and you see what IU
: mean), thats what I mean with mobile.
I don't use my monitor much while driving, so I don't see that it's much of an
issue. I personally quite like the image quality that trinitron tubes deliver,
and prefer it over the shadow-mask style.
Robert J. Dennison
Thanks to everybody for the input.
It sounds like the Sony is the way to go. Fortunately, I have a DELL
P991 kicking around here, which is a Sony Trinitron tube, full
multiscan, SOG capable monitor.
It sounds to me like this bad-boy will work just fine (although I
realize that nobody's willing to guarantee it <grin>). If anybody's
tried this monitor with an SGI Indigo2 before and has any feedback,
I'd love to hear it.
Info on the monitor (should you guys want to check it out for me) can
be found here:
http://docs.us.dell.com/docs/monitors/p991/en/spec.htm
Lemme know if you have any concerns about this monitor and the
Indigo2.
Thanks!
R.
Michael Laajanen
Robert J. Dennison wrote:
> Tony 'Nicoya' Mantler <nic...@ubb.ca> wrote in message news:<nicoya-2D5B83....@news.sc.shawcable.net>...
>
>>In article <u4kac.88044$dP1.2...@newsc.telia.net>,
>> Michael Laajanen <michael.laajanen.no-spam.@telia.com> wrote:
<snip>
>
>
> Thanks to everybody for the input.
>
> It sounds like the Sony is the way to go. Fortunately, I have a DELL
> P991 kicking around here, which is a Sony Trinitron tube, full
> multiscan, SOG capable monitor.
>
> It sounds to me like this bad-boy will work just fine (although I
> realize that nobody's willing to guarantee it <grin>). If anybody's
> tried this monitor with an SGI Indigo2 before and has any feedback,
> I'd love to hear it.
>
> Info on the monitor (should you guys want to check it out for me) can
> be found here:
>
> http://docs.us.dell.com/docs/monitors/p991/en/spec.htm
>
> Lemme know if you have any concerns about this monitor and the
> Indigo2.
>
> Thanks!
>
Since I am in Sweden the link don't work for me and I really can't find
my way into Dells terrible buy site, how to find the search I don't know (:
Anyhow, I tried Google at
http://pcmag.shopping.com/xPC-~PD-21434285~NS-1~linkin_id-3052826
where they list two specs of the P991!! Or I can't I read properly :)
Anyhow I also Googled for a description of the 13W3 for SGI and like
Tony says they are different that the "standard" 13W3 I know of, you can
see here http://www.mycableshop.com/techarticles/13W3SGI.htm
If I where you I would get a 13W3 converter unless you would like to get
a SGI monitor which is maybe cool but I guess they are getting old if
the price is good.
They you just try it(Indigo will not get hurt), if you get a picture
then check if you will see any tendency of "stressed", like the full
Indigo picture is display over less then the full display (horisontally)
that would be an indication of that the monitor can't keep the same pace
as the Indigo(the ~100-130MHz we talked about earlier), apart from that
listen for strange noise(high freq) if nothing like that you have a nice
weekend hacking Irix lucky you :))
What do you US say, "better burn the monitor than let it fade away ... " :)
Good luck
Michael