Am386DX-40 wrote on 2021-08-02, 16:13:
Have you tested for performance difference between original bios and mr-bios?
No unfortunately, though I did some partial benchmarks of the TX486DLC vs. the AMD 386-40 it originally came with, using the MR BIOS. CPU score is low in SPEEDSYS because of a programming anomaly in the benchmark when run on a system with a 387(DX/SX/etc.) FPU is installed. Also on this board, the 1K on-chip cache doesn't appear in the benchmarks I run, despite a very obvious increase in memory write throughput and a general overall reduction in off-cache access latencies in CACHECHK V7 compared with the 386DX-40. (Interestingly, memory copy actually seems to have taken a slight hit with the 486DLC.) Both the CPU internal cache and the MX305 built-in 8K cache, are enabled in BIOS Setup.
Specs: 16MB of 60ns DRAM running at the fastest timing (60ns), ISA bus running at 10.0MHz (40MHz / 4), WD 90C31 ISA VGA card with 1MB (which Speedsys seems to think only 768K is present), Quantum Trailblazer 420AT hard drive, ESS 187x (forgot which specific number exactly) ISA sound card. OS is PC-DOS 6.3, with Windows for Workgroups 3.11 with Wolverine/TCP-IP/32 stack and Win32s installed. Also a 3com Etherlink III ISA ethernet card is installed (and through it, Windows for Workgroups can talk to my Synology NAS).
386DX-40:
The attachment C386MX.png is no longer available
TX486DLC-40:
The attachment 486DLC.png is no longer available
For reference, here's the original AMI BIOS the board came with. Looking through the BIOS it does not appear that proper Cyrix 486DLC identification is included in this particular build of AMIBIOS, though an option for 'Cyrix Internal Cache' is present in the BIOS Setup, so maybe support for the 486DLC was simply hacked in.
The attachment C386MX-AMIBIOS.zip is no longer available
Life isn't long enough to re-enable every hidden option in every BIOS on every board... 🙁