mpe wrote:Thanks. I actually just tried it and got the Am5x86 p75 working. Clearly, it doesn't need Socket 3. It just needs 3.5V 😀
It is slow like hell though at 150 MHz it is only 1.4x faster than 50 MHz. At pure ALU tests it is better but still slower than ordinary VLB-era 486 chipset.
I think slow cache/mem and ISA card is holding it back. Will see if an EISA VGA will be any better...
Which benchmark are you using? If it's graphical, yes, ISA will be a huge bottleneck. EISA will be better when it comes to bandwidth, but chipsets are also ancient compared to VLB/PCI.
If it's not graphical, something on that board needs tuning. Does it support WB cache? And how are the wait states?
I've not done a comparative benchmark of 486 chipsets, but I did do that for So5/7 once. Mem performance differed more than a factor 2 between the fastest (Aladdin IV just beat i430TX) and slowest (UMC 890C), clock for clock with same CPU and RAM. Wouldn't surprise me if differences are just as big with 486.