i wonder if this might help your diagnosis?

http://www.playtool.com/pages/artifacts/artifacts.html

I appreciate the link, but the effect I'm getting is... less sophisticated than what they're picturing. It's white, blocky pixels that refuse to change (another graphics adapter and a second computer on the same screen won't yield this effect) even while the rest of the image loads more or less correctly with some really minor anomalies and distortion. I.e. the game remains playable even with it.

Now, since I have the thing in front of me, I can throw out some more info on the card itself. As I mentioned before, it's an ATI ISA card. There are two part numbers on it though. One is stamped onto the front of the card itself and that one is 1090011541; and the other is on a sticker label on the back and is 1021151343.

Taking a closer look at the card, there is a chip installed in a socket on it. There's some kind of glop on the chip itself, but whether that means it was a stock item covered by a sticker or an after market addition, I couldn't say. Either way, it probably had some kind of label on it and now the goop is pretty much stuck on it. The chip itself has the markings:

27HC256
-90/P
9231 CCA
Taiwan
Microchip

Not sure if any of this information even tells anyone else what I'm dealing with, much less what might be wrong with it. I haven't yet had the chance to try the board with the chip removed. I'm assuming the chip is a RAM upgrade of some sort?

The removable chip is probably for the color management. I have an Orchid ISA card laying around that has a replaceable... forget what it's called, but it affects it's color-depth abilities, for instance: 16-bit vs 24-bit, etc.

Can you make some photos of the card and the screen.

And what is "glop" (dictionary failed on that word). When there is a sticker on it don't remove it, it could be an programmable eeprom and those can be erased by ultra violet light, and the stick is preventing that light reaches the chip.

So, back to your problem: It could me faulty memory on the card. Or a faulty/dirty connection to the memory. Older cards had memory you could remove, maybe cleaning would help. Or there is to less memory than jumpered. But make a photo first.

27HC256 most likely contains the video BIOS.

Actually, I wouldn't use an ISA video card for a P200, except to slow it down. If the mainboard doesn't have PCI slots I'd probably look for a different mainboard/system.

Thanks again for the great feedback. I'll see about getting pictures of the offending card tonight when I get home.

As for getting pictures of the display anomalies, I could attempt to photograph the screen while it's acting up, but I don't know if that'll get the issue across properly.

Given that I have one voice against using ISA graphics cards in a P200, what would I be well suited to throwing in this beast? It's a desktop Optiplex with 2 ISA and 2 PCI slots on an expansion board mounted sideways in the case, but only three of those slots can be in use at any time (i.e. 2 ISA and 1 PCI or 1 ISA and 2 PCI). Presently, I'm toying with a Yamaha OPL ISA soundcard and a Soundblaster Audigy 1 for anything the Yamaha refuses to work with. At one point, I contemplated tracking down a Graphics Blaster for strict nostalgia points as that was the first piece of hardware I ever bought for myself to upgrade a machine, but I have zero recollection as to which model I bought at this point or if it would even do me any good over the on-board Optiplex graphics, which seem to be doing the job just fine.

At this point, if I can figure out what's wrong with it and resolve it, the ATI is poised to potentially end up in the 486 I'm working on; but that's only if it turns out to be an upgrade on the card already in it (pics of that card are in the thread I created about the 486).

So, basically, this is super low priority if the P200 can't even benefit from using it AND then the question broadens to what I'd be well-suited to throw in for a system that is being primarily used for DOS gaming and earlier Win 98 games.

All the same, I will toss up pics of the ATI tonight because now I'm curious as to what's going on with it.

Oh, and sorry for my use of "glop" earlier. I forget that this is a truly global community and euphemisms like that mean nothing to anyone outside of my locality. "Glop" in this case refers to a combination of old adhesive and really badly deteriorated label/paper still stuck on the chip in question. I'll pop it off the board and get pictures of it on its own when I update tonight.

Runicen wrote:

Given that I have one voice against using ISA graphics cards in a P200, what would I be well suited to throwing in this beast? It's a desktop Optiplex with 2 ISA and 2 PCI slots on an expansion board mounted sideways in the case, but only three of those slots can be in use at any time (i.e. 2 ISA and 1 PCI or 1 ISA and 2 PCI). Presently, I'm toying with a Yamaha OPL ISA soundcard and a Soundblaster Audigy 1 for anything the Yamaha refuses to work with. At one point, I contemplated tracking down a Graphics Blaster for strict nostalgia points as that was the first piece of hardware I ever bought for myself to upgrade a machine, but I have zero recollection as to which model I bought at this point or if it would even do me any good over the on-board Optiplex graphics, which seem to be doing the job just fine.
\

Then why not use a PCI card? Even a slow PCI graphics card is faster than the fastest ISA card.

smeezekitty wrote:

Then why not use a PCI card? Even a slow PCI graphics card is faster than the fastest ISA card.

Well, the short answer at the moment is that I don't have one - so onboard graphics it is. Since I had this ISA card floating around, I figured I'd give it a whirl and it was a dead end. I'll cast around the board for recommendations as I'm sure that's been covered to death. I'm assuming I should stop short of a 3d accelerator and hold off for a PIII or something of the like to pair one of those to, right?

As for my ignorance on ISA graphics, I didn't start messing with the insides of PCs until after ISA was an antique, so it was all PCI and then PCI and AGP when I got started with this mess. When it comes to those old slots, I know that sound cards in ISA are revered, but that's about as deep as my knowledge goes. In the meanwhile, if this card can be "fixed," it may be a good upgrade for my 486.

Oh, and as promised, I do have pictures of the card and the graphics anomalies. I'll do two posts to split them up more logically. The attached pictures here are the graphics anomalies as they present in Wolf3d. In the menu, it's a static set of dots towards the top of the screen. Once in game, they tend to flash as things move and update, but they remain more or less in static position, which is how the game is playable regardless.

I should point out that the pictures were taken with my phone and the floors in-game and on the title screen are colored normally. Something about the exposure made them look bright white.

Here is the card itself in all of its full-frontal glory. The removable chip I mentioned is installed.

The same card from the back.

And here is the chip on its own, with the "glop" on top of it plain to see. Like I said earlier, it looks like some kind of heavy label was very clumsily removed from it at one time or another.

Same chip from the bottom. Surprisingly clean on this side.

Artifacting like that can be a sign of a video chip on it's way out. You might get a clear desktop, but as soon as you load up a game it starts glitching. I've owned 3 video cards that did that and all were unfixable. Playing around with drivers and other software installed on the system won't help a broken video card.

Hey I have that ATI isa card, but with a proprietary mouse port and s-video IIRC. If you were happy with that card isa card a S3 Trio64 would be a cheap/common replacement pci card.

Runicen wrote:

smeezekitty wrote:

Then why not use a PCI card? Even a slow PCI graphics card is faster than the fastest ISA card.

Well, the short answer at the moment is that I don't have one - so onboard graphics it is. Since I had this ISA card floating around, I figured I'd give it a whirl and it was a dead end. I'll cast around the board for recommendations as I'm sure that's been covered to death. I'm assuming I should stop short of a 3d accelerator and hold off for a PIII or something of the like to pair one of those to, right?

As for my ignorance on ISA graphics, I didn't start messing with the insides of PCs until after ISA was an antique, so it was all PCI and then PCI and AGP when I got started with this mess. When it comes to those old slots, I know that sound cards in ISA are revered, but that's about as deep as my knowledge goes. In the meanwhile, if this card can be "fixed," it may be a good upgrade for my 486.

As an explanation: Maximum ISA bandwith (at standard clock) is something like 8MB/sec while maximum PCI bandwith is 133MB/s (which a P200 can't saturate, but 70-90MB/s should be possible with a good video card).
I don't know which Optiplex model you have, but all of those which can use a P200 have an S3 Trio64, Trio64V+ or Trio64V2 chip onboard which are excellent choices for retro gaming. Some only have 1MB video RAM which is upgradable to 2MB. (2MB is not necessary for DOS, but nice for Windows.) I recommend you try the onboard video first, if you like you can add a Voodoo1/2 later for 3D.

[EDIT] Oh, and an Audigy 1 is maybe not a good fit. It is somewhat newer than the rest of the system (2001 as opposed to 1996-1998), and I doubt that you'll get better compatibility than with just about any ISA sound card. (And you'll need DOS drivers if you want to use it in native DOS which will eat RAM.) It makes more sense for Windows since you'll get EAX.

The card's pins look really dirty and that may be the cause of the problem. Try cleaning them with an eraser and see if the problem goes away.

Another thing that you could try is setting the 8-bit I/O Recovery Time to 8 and 16-bit I/O to 4 on the BIOS. That sometimes can solve problems with ISA cards.

If there is no flickering, so the pixels just are wrong color, my guess is that it is a palette issue (game might wite palette data too fast for the card to handle it).

So I also suggest increasing 8-bit IO recovery cycles in the motherboard BIOS settings. It does not hurt to max out both 8-bit and 16-bit IO recovery cycles for testing to get things slow enough.

Also if you have BIOS option for "VGA PALETTE SNOOP" or something that sounds similar, also set it to DISABLED.

Once again, thanks to all of you for the great info.

As it stands, I think I'll wait to test this card further (after cleaning the pins) until the 486 is ready for some real software testing. Given that it sounds like an Optiplex's onboard graphics adapter (mine is an Optiplex Gn+ if that helps) is already what I'd want in a standard graphics card anyway, why reinvent the wheel, right?

I suppose I should ask, is there a PCI graphics card that won't cost the gross domestic product of a small tropical country and which will provide decent 3d acceleration for DOS and Win 95/98 games on a P200, or am I mixing my eras too much by going that route? I think I mentioned earlier, once I have the Optiplex and the 486 sorted, my mind is already half on a PIII build for late 90s gaming (i.e. around the time I ducked out of it myself). That said, I just fired up Quake on this beast and it runs in 640x480 with just a little bit of chop. Being able to really let this machine spread out and start processing polygons would be fun.

I was referring to http://en.wikipedia.org/wiki/Dell_OptiPlex#Mo … nological_order
IN that list the video chip is not given for the Gn+, but other sources specify a Trio64V2 with 2MB RAM so that's perfectly fine for 2D.
The Gn+ is one of the later Socket 7 Optiplex models, 430TX chipset, support for P-MMX and SDRAM. Just don't use more than 64MB RAM because of the cacheable area.
Of course there are a lot of fitting 3D accelerators for a P200 MMX. For Win9x a lot of models would be OK, from Riva 128 on.
With 3d acceleration for DOS we are talking about proprietary 3D accelerators, see this thread (which doesn't include 3dfx Voodoo/Glide): 3D Accelerated Games List (Proprietary APIs - No 3DFX/Direct3D)
A Voodoo1 would be fine both for DOS and earlier Win9x 3D games. From the mentioned thread a lot of cards are more or less rare/expensive, the affordable ones would be S3 Virge (be careful to select a good/fast one) or Matrox Mystique (definitely a 4MB one, Mystique 220 is OK, Mystique II not), but both are not recommended for general 3D in Windows. Games with ATI Rage 3D support are nearly exclusively for Windows.