It looks like 2MB. I've never seen 3MB. Although some cards can use dedicated DOS/accelerated mode memory. Like cards with Weitek chips - Diamond Viper VLB or TiGA cards and also some early ATI cards.

My guess: it looks like it has KM424C257Z-6 memory ICs. Just look up the datasheet for the IC and multiply it with the number of the ICs the card has.

But since you have 16 of them, it's probably either 2 or 4MB.

2MB for sure...., 4Mb cards looks like this - much more space needed..... 🤣

Also if you have fast monitor, you can see memory size on 1st boot screen when vga is booting.

Quote from Diamond PR news 1993

The standard list price for the Stealth Pro with 2MB of memory was reduced from $499 to $449, and the 1MB version was changed from $349 to $299.

So they been selling 1MB or 2MB models.

Thanks. I did try to see the 1st boot screen, but both monitors that I tried it with were not fast enough. Tried with reset button too when monitors were already showing picture, but that didn't work too.

Baoran wrote:

I bought this card Bought these (retro) hardware today about a week ago, I thought I bought 2Mb card but now I am getting conflicting info from programs. Pctools SI9 says that it has 2Mb ram, but both NSSI and speedsys say that it has 3Mb ram.
How do I find out what is correct for sure? Does 3Mb card even exist?

3MB cards exist:

That *BIG* VLB card is a Miro Crystal 24S with the same S3 928 chip and 3MB of VRAM.

But I doubt your card has 3MB of VRAM. It has 16 RAM chips, which isn't divisible by three. I'd expect either 6, 12 or 24 for 3MB.

First thing to check when getting confused about RAM sizes is bits & Bytes. You're saying "2Mb" and "3Mb" where you probably mean "2MB" and "3MB". Maybe your tools are referring to something else. Post a copy/paste of the info, that might clarify things.

It was sold to me as 2MB card, so it just confused me when NSSI and speedsys said it had 3MB. Any idea where they would get that number from? It seems to be part of VBE info.