Auto Config: Enabled
Dram Read Burst: 2/2/3 (Auto selected)
DRAM Fast Leadoff: Disabled

Auto Config: Disabled
Dram Read Burst: 2/2/3 (Manually selected)
DRAM Fast Leadoff: Disabled

All I changed was the Auto Configuration from Enabled to Disabled. No other settings or timings changed, yet the speed went down in Speedsys.

Auto Config: Enabled
Dram Read Burst: 1/2/3 (Manually selected)
DRAM Fast Leadoff: Disabled

Here I tightened timings, but it didn't result in any improvement.

Auto Config: Enabled
Dram Read Burst: 2/2/3 (Auto selected)
DRAM Fast Leadoff: Enabled

And here I used the Autoconfiguration again, but manually changed DRAM Fast Leadoff to Enabled, which improved performance.

And here's a picture of the memory module I'm testing with. I'm using two of these for a total of 128MB.

Few updates:

- I still haven't figured out why switching from Auto config to manual in BIOS reduces performance. I tried two different brands of RAM. If anyone has a theory on this I'm all ears
- I tested every possible item in BIOS settings and made the following improvements/observations:
- DRAM Fast Leadoff: while setting this enabled improved memory throughput from 77 to 79 MB/s, I wasn't able to pass memtest86 and ended up disabling this feature. I tried different RAM modules, none passed.
- Read Around-Write: enabling this resulted in significant speed gain. Memory throughput went from 77 to 93 MB/s
- CPU-To-PCI Write Post: enabling had no impact on Speedsys memory test, but Quake 2 doubled FPS: Glide 800x600 went from 24.4fps to 40.2 on Demo1, and 11.5 to 21.5 in Crusher.
- Using 50ns vs 60ns RAM resulted in no speed improvement or stability improvement
- I had problems passing MemTest86 with non-matching RAM modules. Currently I'm using a matching 4x32=128MB 60ns set that works fine. 2x64=128MB 50ns also works fine. I tried 4x64=256MB set where three modules were 50ns and one was 60ns and got errors, even though this combo works well in VS440FX PPro board. Tried 2x32MB 60ns and 2x64MB 50ns for total of 192MB and it also failed. So at this point i'm going to stick with the 4x32=128MB 60ns setup until I find matching higher capacity set, I have no urgency for that as 128MB is working very well right now in Win95, NT4 and even Win2k.

why is fast dram refresh and/or dram ras only refresh never enabled ?
also
dram ras precharge time ? can you set it to 2 ?

weedeewee wrote on 2021-08-18, 18:46:

why is fast dram refresh and/or dram ras only refresh never enabled ?

Fast Dram Refresh: enabled reduced performance e.g. bandwidth went from 77MB/s to 68MB/s
Dram RAS only Refresh: enabled reduced Quake 2 performance from 40.2fps to 34.3fps. SpeedSys bandwidth test was not affected

weedeewee wrote on 2021-08-18, 18:46:

dram ras precharge time ? can you set it to 2 ?

the lowest possible setting is 3

could be your bios only uses 60 NS when auto but when disabled uses 70ns. Could be some hidden settings in AUTO shenanigans. You might need to mod the bios to enable it.

Warlord wrote on 2021-08-18, 18:58:

could be your bios only uses 60 NS when auto but when disabled uses 70ns. Could be some hidden settings in AUTO shenanigans. You might need to mod the bios to enable it.

I tested that as well, but that performed worse than the MANUAL settings. At this point, I'll just let that be a mystery. I think I set it up to its maximum potential the board allows and will have to be content with that...that didn't sound right, I'm actually very happy with the performance.