That looks like a very old card. Meaning it could be a slow revision / version. This is just my generalisation, but I found that the really old looking cards do perform slower and the highly integrated ones, are more modern, and do better. What does your Trident look like?

Here is my Trident pic.

Date on Tseng chips and PCB suggest year 1992, date on Trident chips suggest year 92/93 and 94.

Unfortunately my Trident is broken, it displays thin vertical lines every few pixels 😐

opiate wrote:

So it probably is 1MB, but when i decided to check few software it only showed 256/512 KB results for VRAM, and i've read somewhere that for some reason it is normal (is there a program for DOS/WFWG that can tell me accurately how much VRAM i have?)

I'm no expert for this kind of things, but I think that's normal, as you said.
The normal VGA could *normally* only have 64KiB, 128KiB or the maximum amount of 256KiB.

I vaguely remember there even was some kind of VGA register that could have helped to determine if a card had 64KiB or 256KiB (extended memory register ?)
Though probing the memory was probably a safer method (how long/far could a specified amount of data be copied and retrieved inside of the 256KiB range).

I think that's why older programs like CheckIt! do say a VGA card has 256/512K (meaning 256KiB or more):
512KiB was about the maximum that could be installed in early 80s card designs (they had free sockets for another 256KiB).
Anything beyond is/was usually covered by SVGA or VBE specs.

Speedsys might be able to query information about the actual video memory size via VBE BIOS (if available).
The original (native) VBE 1.x drivers for the chipsets may also show the true memory size.

Don't know about the performance, but that Tseng card has 512KB of RAM. Each chip is 256K x 4 bit = 128KB, so with the 4 chips you have 512KB. Also, it seems to have sockets to expand the RAM to 1MB.

Vendors have always loved putting cheap ram- and lots of it- into low end cards to inflate their percieved value.
512MB Geforce 6200, etc.

opiate wrote:

Unfortunately my Trident is broken, it displays thin vertical lines every few pixels

Try a different monitor, you'd better get a CRT.
On a 386 the graphics card won't make much of a difference in games anyway unless it's really crappy and extremely slow.

Well, as TheMobRules point out, it is in fact 512KB card, Univbe confirms it [pic attached].

CRT is out of the question, my 'second half' forced me to remove them from the house [only 2 amiga crt's remained].

Thanks for the help guys, i decided to stay with Tseng card since in games performace is the same as in Trident.

Jo22 wrote:

The normal VGA could *normally* only have 64KiB, 128KiB or the maximum amount of 256KiB.

Less than 256k is extremely rare, and with less than 256k, various of the features considered as 'standard VGA', would not work, such as Mode X.
I doubt that any non-IBM VGA cards were ever made with less than 256k.

opiate wrote:

Thanks for the help guys, i decided to stay with Tseng card since in games performace is the same as in Trident.

Actually, it would be a smarter choice to use the TVGA9000C because game performance is identical. With both cards you're hitting the limit of the bus and the 386 can't push more bytes through it. But the important thing is that the TVGA9000C is maxed out by a 286/386 anyway and will slow down faster machines. The ET4000AX however will perform better in faster machines, so you could put that one into better use.

I don't think I have ever heard of a VGA card with less than 256kb RAM. If it had less, I don't even know that it could be considered VGA....it would be something in between VGA and MCGA.

You are correct, VGA has 256 kb minimum, otherwise it's not VGA. You can not display 640x480 @ 4 bit with less, as it does not fit. Actually, VGA can only ever have 256 kb, because more means it is SVGA already (capable of 800x600 or 640x480 @ 8 bit for example).

Anonymous Coward wrote:

I don't think I have ever heard of a VGA card with less than 256kb RAM. If it had less, I don't even know that it could be considered VGA....it would be something in between VGA and MCGA.

Any idea how much memory MCGA has? In theory it could make do with 64k.
I'm not sure if that could work for real VGA. In unchained mode, you get 4 'bitplanes' of 64k each, and each bitplane contains each Nth column, with N mod 4.
You select which bitplane(s) to write to with a separate register. It's basically a superset of EGA, which has 4 bitplanes as well, but they are actual bitplanes, where VGA stores pixels as bytes, which act as palette index.

In chained mode (regular 320x200 mode 13h), the bottom 2 bits of the address select the bitplane to write to. I'm not sure how the memory is laid out in practice. If it is the same as in unchained mode (line 'Mode X', although people generally also use 320x240 rather than 320x200 in 'Mode X'), then that would mean you get a 'sparse' memory layout, rather than all pixels packed together, and effectively you'd still need 256k of memory to display a 320x200 screen.

In that case, a 64k VGA card would be little more than an EGA card that can be connected to a VGA monitor.
I guess it would make more sense if at least 320x200 mode worked in 256 colours with 64k, so it was at least equivalent to an MCGA card. But I'm not sure if that's technically possible with the VGA circuitry.

As far as I can remember, MCGA is 64k. Only 2 or three systems ever used the MCGA standard, and none of them were upgradable.

Too bad MCGA was not EGA compatible, eh? As I recall, this was an annoying problem as you would have to fall back to CGA mode if the 256 colour software you ran required a proper VGA card.

Anonymous Coward wrote:

Too bad MCGA was not EGA compatible, eh? As I recall, this was an annoying problem as you would have to fall back to CGA mode if the 256 colour software you ran required a proper VGA card.

It made sense though, since EGA had quite a complex ALU on there, to manipulate individual bitplanes, and it also supported hardware scrolling and such. VGA is only a small upgrade from EGA really.
MCGA is quite a good name: It's as 'dumb' as CGA, in that it is nothing more than a framebuffer. They just added the VGA palette option to it, so you get a 256 colour 'CGA' mode.
Maximum gain from minimum effort.

I suppose the majority of early VGA games are actually MCGA, and merely use the card as a framebuffer. I recall that games that use some form of 'scrolling', like Monkey Island and such, just did bruteforce memcpy operations with the CPU. Very slow and not smooth at all, but works perfectly on MCGA.
It's only the games that use Mode X or something similar, that would not work on MCGA. I can think of F29 Retaliator, Wolfenstein 3D, DOOM, but I wonder how many other games use clever VGA trickery instead of just treating it as a dumb framebuffer.

Yeah, sometime i that MCGA could support proper PCjr/Tandy modes as those modes are framebuffer too, and not 4-bitplanes.
I do curious to why IBM decided to not provides backward compatibility to PCjr modes for EGA and beyond.

The problem with PCjr is that the videocard shared the main memory, and you could select any memory bank to use as video memory.
This is different from the standard PC architecture, where the low 640k is dedicated system memory, and video memory is in the upper memory blocks.
So you could only have partial support for PCjr graphics on a regular PC. Only if the software doesn't try to do any bank switching or whatnot, and it only accesses video memory through the B800h-window.

Not to mention that most games with PCjr graphics would assume they run on a PCjr machine, which also means PCjr audio and special keyboard handling and such.
So PCjr games wouldn't work on a standard PC anyway.
We've found something similar when developing the Tandy Compatible Sound Adapter. It's an ISA card that adds an SN76489 chip at port C0h, which is compatible with a PCjr. But in practice most games have to be patched because the PCjr audio is usually hardwired to PCjr graphics in some way. So you can't just use PCjr audio with regular CGA, EGA or VGA graphics and PC-compatible keyboard handling and such.

Haven't you changed any jumpers on the Tseng card? Some Tseng cards have a jumper for 0/1WS memory operation