Is it 512kb? Check PCI/ISA divider.

No. It is 1Mb card and divider was 1/4 like I always have used with 33Mhz FSB.

Jumpers?

Do you mean the jumpers on the video card? I don't know what they do and I have not touched them since I got the card couple years ago.

Looks like you should.

Do you know what the jumpers do?

Not on Tseng cards, but from my experience with Trident and Western Digital cards, one of them is probably used to enable/disable FIFO i.e. drastically improve performance.

Changing JP3 on the card did speed up it a little, but it is still very slow. Now I tried to match phil's results.
https://imgur.com/CoLrmnu
https://imgur.com/ThHTk69

My results in doom benchmark were 13.4 FPS for 66Mhz cpu and 10.6 FPS for 33Mhz cpu
Phil's results are still almost 50% faster especially with 66Mhz.

I think there are two possibilities here:
1) The ET4000AX is very slow for some reason
2) The 486 is very slow for some reason

I would start by testing the ET4000AX in a known good/fast PC, or by using a known good/fast card in your 486.
It could be that your 486 is just slow because it has no/fake cache on the motherboard, in which case it will be slow no matter what card you use.

Scali wrote:

I think there are two possibilities here: 1) The ET4000AX is very slow for some reason 2) The 486 is very slow for some reason […]
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I think there are two possibilities here:
1) The ET4000AX is very slow for some reason
2) The 486 is very slow for some reason

I would start by testing the ET4000AX in a known good/fast PC, or by using a known good/fast card in your 486.
It could be that your 486 is just slow because it has no/fake cache on the motherboard, in which case it will be slow no matter what card you use.

The motherboard is very fast with any PCI video card (33Mhz 16 FPS and 66Mhz 26 FPS). but it becomes slow like that when I put that ISA video card there.
So since I can't at the moment test the card with another 486 motherboard, I was wondering if it is possible that something about the motherboard having a pci bus can make ISA video cards slow?

I tested my ET4000AX a while back with a 486DX 33 MHz & 486 DX2 66 MHz on different 486 motherboards and the results can vary quite a bit, depending on (but not limited to):

• Amount of memory on your motherboard
• Secondary (L2) cache and the size
• Chipset of the motherboard
• Amount of RAM on your graphics card
• Whether you are booting up in real mode of virtual 86 mode (with EMM386.exe loaded)
• BIOS (CMOS) settings of your motherboard (RAM & cache timings, etc.)

On my "hybrid" 386/486 motherboard (with an OPTI 495XLC chipset), I got worse results than on a dedicated 486 VLB based motherboard.
Best I managed to get (in real mode) on the 33 MHz CPU was 10.4 fps and on the 66 MHz CPU was 15 fps.

I performed another test with the same CPU's on an ASUS VL/I-SV2GX4 motherboard but, using a Cirrus Logic CL-GD5422 1 MB ISA card (the CL-GD5422 is more or less comparable in performance to an ET4000AX).
There I managed to get 13.9 fps with the 33 MHz CPU & 24.2 fps with the 66 MHz CPU.

I understand that those things make a difference, but should a system that is the fastest 486 with pci cards that I have seen become slowest when I just switch a pci card to that isa card and change absolutely nothing else?
Cache, ram, chipset, config.sys/autoexec.bat and bios settings all stay the same.

Considering that I got 13.9 fps on my 33 MHz 486DX & 24 fps with my 66 MHz 486DX2 with my GL-GD5422 16-bit ISA card on a VLB motherboard, and your PCI graphics card barely outperformed my ISA card on a PCI based motherboard, I would say that your problem is most likely with your motherboard.

Just as a matter of interest, what 486 motherboard do you have?

LS-486E
There is a picture in this thread. Re: 486 and hard drive size limit.
I don't know how it compares to other motherboards, so all I am saying that it is fastest 486 motherboard I have. It beats them by at least 10% when using same cpu.

Baoran wrote:

LS-486E
There is a picture in this thread. Re: 486 and hard drive size limit.
I don't know how it compares to other motherboards, so all I am saying that it is fastest 486 motherboard I have. It beats them by at least 10% when using same cpu.

I have the same motherboard as well and it's a very nice 486 PCI motherboard.
I suggest you take a closer look at your CMOS settings.

jesolo wrote:

Baoran wrote:

LS-486E
There is a picture in this thread. Re: 486 and hard drive size limit.
I don't know how it compares to other motherboards, so all I am saying that it is fastest 486 motherboard I have. It beats them by at least 10% when using same cpu.

I have the same motherboard as well and it's a very nice 486 PCI motherboard.
I suggest you take a closer look at your CMOS settings.

Any chance you could test ET4000AX isa card on yours or some other isa video card?