Only if you can change the chache speed and waitstates in bios somehow. If you pu a fastes chip somewhere it does not do anything, if you can not run it faster. It is this way with CPU-s, memory, and cache.

Cyberdyne wrote on 2020-11-03, 13:11:

Only if you can change the chache speed and waitstates in bios somehow. If you pu a fastes chip somewhere it does not do anything, if you can not run it faster. It is this way with CPU-s, memory, and cache.

There is options for memory 2-1-1-1 or 3-2-2-2. and only to disable the cahce or enable it. Just wondering really why the PBC chips are so much faster than the tag ram, while on 486 cache and tag it was the other way around.

One other thing I noticed, this motherboard also has a COAST slot. I disabled the 256KB onboard PBC with jumpers and used a cost stick with 256KB and winbond 7ns chips. When I benchmark this in speedsys, the L2 speed is 17MB/S slower compared to the onboard PBC cache (even though they are exactly the same size and timings). All I can think is having the PBC chips soldered on to the motherboard is faster than using exactly the same in the cost slot.

No it is fine.

486 boards are working with lower latencies and also each cache line was half in size.

Also the 100 MHz bus on 430FX doesn't sound right. The chipset doesn't support that. That would lead to 50 MHz PCI bus which wouldn't be healthy. Are you sure it is really bus speed and not CPU speed?

Many Intel motherboards assume that when you insert a module into the slot you are extending the cache. That's why their program chipset has to insert extra cycle to allow for bank turnaround which would lead to slightly slower bursts. Perhaps that's why you see the difference? Your coast stick could also flip some other bits. You would need to read how the actual programming of the chipset. BIOS settings can be overriden.

mpe wrote on 2020-11-03, 14:43:

Also the 100 MHz bus on 430FX doesn't sound right. The chipset doesn't support that. That would lead to 50 MHz PCI bus which wouldn't be healthy. Are you sure it is really bus speed and not CPU speed?

Many Intel motherboards assume that when you insert a module into the slot you are extending the cache. That's why their program chipset has to insert extra cycle to allow for bank turnaround which would lead to slightly slower bursts. Perhaps that's why you see the difference? Your coast stick could also flip some other bits. You would need to read how the actual programming of the chipset. BIOS settings can be overriden.

The board has jumper settings labelled FS0, FS1, FS2 for speeds of (25mhz, 33.3, 40, 50, 60, 66.6, 80, 100mhz). Next to it is a REFCLK with 14.317 Mhz.
I can boot a P133 at 200mhz using jumpers FS0, FS1, FS2 all jumpered to 1-1-1. So this would be 100mhz fsb x 2. Problem is it hangs when loading win98.

brand /model of the motherboard? And a pic of the whole motherboard?

cyclone3d wrote on 2020-11-03, 16:54:

brand /model of the motherboard? And a pic of the whole motherboard?

Motherboard is GA-586ATMP rev 6. It's a bit obscured in the case , awkward to picture the full board without taking everything out. One thing I noticed, even though this is an old 430fx chipset, it says socket 7 on the white cpu socket. I was sure it was a socket 5 motherboard.