I have a A1GX, in an Acer with a Ali M1429G, maybe it have some similarity :
I do have a Ti486DX2 66Mhz or 100Mhz(cache won't work at 50mhz fsb, need faster chips)
You only mentioned benchmark is Speedsys Memory Throughput, here mine with corresponding FSB speed : I get 24MB/s (33fsb), 16.9MB/s(40fsb) and 25.5MB/s(50fsb).

1 - There is no setting for the cache except "Enable/disable" in the first page of "Advanced System Configuration". If the option is gray-out, Go in "Basic system configuration" and disable "Auto configuration mode and fast boot mode".
2 - Only use 33Mhz or 50Mhz BUS. That one is also important. Setting to 40 or 50 include setting a divider on the memory/isa bus so if you set 40Mhz, the memory will slow down, like if you set it to 25.
3 - If cache is enable and properly set with the jumper and it's not showing, then it is likely that one of more of youre cache chip are defective or that something is wrong with the cache related parts/traces on the board.

I have extracted the VBIOS of my BIOS too and I plan to try other BIOS and swap it too once I get my hand of some eprom and a competent programmer, That BIOS is just too anemic and there is no memory adjustement options. The only cool thing with it is that you can CTRL-ALT-ESC from DOS and go in the BIOS without rebooting, shame the bios is so crap.

In any case, test you're cache SRAM and stay clear of 40Mhz bus speed.

Edit : If there is no cache option at all in the BIOS, it's likely to be automatic, system test it at boot and enable it if it pass the test. There is no need an option as if it's enabled and there is no cache, it will detect there is no cache. The option in the BIOS is more... To disable the cache, when you have cache.

Edit2 : You are right about the 3.3V, you don't seam to have a voltage regulator on that board. The A1GX do.

Thanks for the info, so the mobo is just slow and needs bios modding. I was comparing performance to my QDI V4S471 and Asus PVI-486SP3 mobos which can do almost double the 3DBench scores with same CPU. And memory throughput is over 50MB/s on both.
256KB cache works, it gives a little boost.

I have UV light and eprommer, maybe I'll start trying different AMI or Award BIOS images from different motherboards and use ISA display card (ET4000), and when I found one that works I'll need to figure out how to get vbios in there too.

MR BIOS has that ctrl+alt+esc too, really handy. Used MR BIOS in one of my 386-motherboard.

dj_pirtu wrote on 2023-04-02, 07:45:

Thanks for the info, so the mobo is just slow and needs bios modding. I was comparing performance to my QDI V4S471 and Asus PVI- […]
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Thanks for the info, so the mobo is just slow and needs bios modding. I was comparing performance to my QDI V4S471 and Asus PVI-486SP3 mobos which can do almost double the 3DBench scores with same CPU. And memory throughput is over 50MB/s on both.
256KB cache works, it gives a little boost.

I have UV light and eprommer, maybe I'll start trying different AMI or Award BIOS images from different motherboards and use ISA display card (ET4000), and when I found one that works I'll need to figure out how to get vbios in there too.

MR BIOS has that ctrl+alt+esc too, really handy. Used MR BIOS in one of my 386-motherboard.

That is what I was able to achieve so far by modifier M1429G registers. I don't know if the M1429 have the same register for what I patched so far but I could help you improve it, maybe.

Stock (Note that the merory bandwidth on top left missing from that screenshot was about 62MB/s)

Patched

I was also able to make the 40Mhz one less atrocious (~match what I get on 33Mhz stock )
Doing more research still.

Here is the current thread on where I will continue to post relevant things about Acer boards using M1429/G
Help wanted --> ALI M1429/M1429G : Need peoples with M1429 board that have a BIOS for adult to dump chipset registers