It looks like video DAC related issue. I'd try to boot PC into clean DOS (all drivers/programs disabled) to rule out software related issues 1st.

Looks like palette access error.
Such glitches are typical of bad buffering.
I am quite sure the cause is the old tantalum caps.
I'd suggest to replace the tantalums on your Acumos (acceptable) board instead of buying a Trident (bad) card.

Edit:
Look carefully at the picture of your card, see the vertical stripe pattern. Such is surefire indicator of bad caps.

retardware wrote:

Looks like palette access error. Such glitches are typical of bad buffering. I am quite sure the cause is the old tantalum caps. […]
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Looks like palette access error.
Such glitches are typical of bad buffering.
I am quite sure the cause is the old tantalum caps.
I'd suggest to replace the tantalums on your Acumos (acceptable) board instead of buying a Trident (bad) card.

Edit:
Look carefully at the picture of your card, see the vertical stripe pattern. Such is surefire indicator of bad caps.

Do you mean on-screen? I had wondered about that. I don't have a soldering iron or any experience. I might get a slow trident whilst I move house and then I can think about learning to solder. I have a PCI ET6000 for my fast DOS PC anyway.

SSTV2 wrote:

It looks like video DAC related issue . I'd try to boot PC into clean DOS (all drivers/programs disabled) to rule out software related issues 1st.

It is already in pure DOS, I just did a fresh install. Not even sound drivers installed at this point!

Hi, please tell what computer you are using - If it is a 486 or 586, there's a chance enabling/disabling "Video Palette Snooping" in CMOS Setup couldl fix this issue.

I think this only applied to PCI video cards. However toggling the setting is certainly worth a try.

Could this be caused by messed up color settings on the monitor perhaps? Have you tried a different screen or the color settings of the screen?

root42 wrote:

I think this only applied to PCI video cards. However toggling the setting is certainly worth a try.

Could this be caused by messed up color settings on the monitor perhaps? Have you tried a different screen or the color settings of the screen?

I've used the screen for a variety of uses this week (Windows 7 PC, second monitor on laptop, Dreamcast) and it's been fine with everything else. All the other colours look OK too, it's just "reds".

Jo22 wrote:

Hi, please tell what computer you are using - If it is a 486 or 586, there's a chance enabling/disabling "Video Palette Snooping" in CMOS Setup couldl fix this issue.

It's a.... this:

386SX 40MHz. 4MB of RAM, using a CF card for storge and Gotek floppy emulator. I was using a CT3910 AWE32 (it's my only soundcard with real OPL sound).

.........................

I can either get a slow Trident for £10 (again... this is on a 386SX that can barely play Wolfenstein 3D with a good graphics card 😜) or coincedently another Acumos AVGA 2 for £35. I kind of don't want the same card twice thought, that's boring!

Only the reds you say? Maybe one of the components in front of the VGA out is broken. Like retardware siad: tantalum caps. Or the ceramics or diodes maybe? Perhaps you can test them.

Almoststew1990 wrote:

I've tried reseating the card many times. Rarely, it will fix it. Same for a trying it in a different slot. I might have to reseat it 5 times for the colours to come out correctly but if I then leave it alone and seated, it will be fine until I disassemble the PC. Is it my motherboard, or the card? Do I need a new card? That be a shame as it is reasonable card for ISA. Here is the card (can't remember the model at all but you guys recommended it) :

Check the back of the card for any pins that might be touching, I had a similar problem with a Western Digital ISA VGA card from around the same time period - some of the pins on the back were touching because they weren't cut as short as on more modern cards, bending them back to being straight fixed it.

Having an ISA Trident as a back up/fault finding card is a good idea I've found. At least you have a complete working system that way while repairs are being done.

I second that. The Trident 8900D was a good card, actually. It had FiFos (?) like the ET4000 and could change to CGA/EGA and Hercules modes via mode utility.
And it was very widespread (!=popular) and reasonable compatible. That's one of the reasons DOSemu had choosen that Trident line for its VGA core, I believe.

"The emulator emulates a basic Trident TVGA8900C graphics card. All standard VGA modes are emulated, most VGA hardware features (mode-X, 320x240 and so on),
some Trident extensions, and on top of that many high-resolution VESA 2.0 modes, that were not present in the original Trident card. Some (very few) programs,
such as Fast Tracker, play intimately with the VGA hardware and may not work. As vgaemu improves these problems should disappear."
Source: http://www.dosemu.org/docs/README/1.4/x553.html

If it comes to old adventure games, like these AGI/SCI0 games from Sierra, an ISA card is handy.
Some animations aren't working properly on PCI cards, providing a wrong atmosphere to the game.

There was a discussion about this years ago here on Vogons.
I'm sorry, can't remember the thread name of it anymore. 😢

Found this thread wrt Cirrus GD5429 vs T8600D cards Cirrus Logic CL-GD5429 vs Trident 8900D - disappointing

retardware wrote:

Edit:
Look carefully at the picture of your card, see the vertical stripe pattern. Such is surefire indicator of bad caps.

Interesting, I have an AVGA2 card which is very similar to the one the OP has, but mine has a green PCB and says "Made in the USA". The colors are good, but it displays the same vertical bands issue as shown in the screenshot posted. It happens on both LCDs and CRTs, altough it is more noticeable on LCDs.

I always thought it was just a poor quality DAC or something like that. Do you think it may be fixed by replacing the tantalums on the card?

many old vga cards heve those strips, it's not the caps but their DACs and surrounding circuits... 99% of times they are fine on CRT screens so it's just the way they were made back then...

Bumping my old thread because I did get a new AVGA 2 card... and it has the same issue! Do you think I am just unlucky, or maybe it's a weakpoint on these cards? or does this now point to the motherboard?

Apparently Acumos AVGA2/Cirrus Logic 5402 aren't very stable cards to begin with, because they had to rely on motherboard oscillator, which can cause problems. I think underclocking your system to 33 or 25 Mhz could help.

I have bought a very similar Acumos AVGA2 videocard today:

However, for me the 'Monkey Island' palette is displayed correctly:

So that should have been some motherboard falut. Or maybe even a broken version of the game?

Thread bumpity time.

The card started giving me the same issues again.

I bought a Trident 9000C to see if it did the same thing. Weirdly, it did!

I went into the BIOS and turned on Video memory shadow something something. Didn't help.

I tried "another version" of the game. It now works perfectly.

On the one hand, FML! On the other hand, yay, now I can play Secret of Monkey Island!

There is nothing wrong with your game and your graphics adapter. There existist two versions of the game, EGA and VGA - the second looks better.

Lol