can you post some pics?

Sounds like a monitor problem to me. The S3 Trio cards are very compatible. The Virge cards are not so compatible - but since you're getting the issues with both the Trio and the Virge I'd say check your monitor.

Does this happen every time a game switches to VGA 320x200 256 colors?

duke3d you can change the resolution to higher svga through the setup may be worth a try as well to see if it happens on different resolution

Here are some photos. I've tried another CRT and a LCD with the same results.

That looks as expected to me. Have you played the original versions before or only newer ports with better graphics?

Honestly I recently got into these old DOS games I used to play as a kid. I don't recall how they used to look since its been decades since I've played them. I thought maybe I didn't set something up right with the graphics. I don't remember everything being so "pixelated" but then again I was 10. Are "newer ports" something that makes these graphics better? I don't mind the original look as its nostalgic to me but I'm curious if the graphics can be improved in DOS. Thanks.

haha that looks as its supposed to, with duke3d u can go setup and video modes and set 800x600 svga pentium 200mmx should handle it all right that will be a big visual upgrade. Out of luck for doom, perhaps dosbox does some smooth scaling otherwise u need to find open ports and remakes. there was quiet a few of duke3d but u need alot more powerfull hardware then a pentium 1 for those

For DOOM, there are some DOS ports with high-res capabilities.

Thanks for the replies. I'm glad to know everything is normal and my hardware isn't the problem. I was thinking about installing win95 or 3.1. Any issues with installing either of those os with dos games?

Most DOS games will not work under Win3.11 (which is not really an OS, more like a GUI on top of DOS).
Most DOS games will work under Windows 95, and Windows 95 also has a pure DOS mode which is for all practical game-related purposes identical to DOS 6.22.

But if you only want to play DOS games, there is little point in installing either of those.

Yes, those look as they should.

DOS games generally use 320x200 resolution, which is not really all that much, and is better suited (in my opinion) to 2D platformers than it is to 3D first person shooters like DOOM and Duke3D. Yes, you can get "source ports" of DOOM which have the capability for higher resolutions, and Duke3D lets you go up to 800x600 if your CPU and video card can handle it. With your setup, you should be able to do this with reasonable framerates, or at least 640x480.