@Baoran
I don't know about the comparison you are interested in but I tested a PII some time ago:

Geforce2 MX 400 64Mb // Jetway 993AN VIA Apollo Pro 133 // 3DMark99 // 1024x768x16

CPU // video benchmark // cpu benchmark
233 MHz PII SECC 233 - 3.5xfsb66 // 1459 // 2153
233 MHz PII SECC @ 200 - 3xfsb66 // 1328 // 1900
233 MHz PII SECC @ 166 - 2.5xfsb66 // 1147 // 1616
233 MHz PII SECC @ 133 - 2xfsb66 // // 641 // 1156
(nb cache is disabled at 2x clock)

for comparison:
933/133 MHz PIII SECC // 3815 // 10909

appiah4 wrote:

Baoran wrote:

appiah4 wrote:

There are DOS games that go bonkers when the CPU is clocked beyond (or is it at?) 200MHz.

Is it about clock speed or actual speed of the cpu though?
I don't know how 133Mhz 486, 133Mhz Pentium and 133Mhz Pentium II cpus compare to each other when it comes to actual cpu speeds though? IPC are different, but not sure how much.

It's specifically about the clockspeed.

Hmm I think it is related to IPC; I can disable L1 and L2 caches on anything running over 200MHz (such as this PIII 1GHz) and it will run Jazz Jackrabbit just fine. Lotus 3 runs fine as well, and running in Alone in the Dark gets way easier.

That 200mhz limit is commonly found in games developed in TP7. Jazz Jackrabbit is one, and it can be patched to resolve the issue.

Baoran wrote:

I thought lowest multiplier you can go with pentium II is 2x. At least I couldn't go below 133Mhz.

You can go 100MHz with 2x multi and 50MHz FSB for unlocked PIIs on the right board.

You can even go slower to fast 486 speeds, around 40 Speedsys score by forcing L1 Write-Thru cache policy on the right board, as well.

With all caches disabled, you can hit 286 territory and slow 386 speeds, too.

j^aws wrote:

You can go 100MHz with 2x multi and 50MHz FSB for unlocked PIIs on the right board. […]
Show full quote

Baoran wrote:

I thought lowest multiplier you can go with pentium II is 2x. At least I couldn't go below 133Mhz.

You can go 100MHz with 2x multi and 50MHz FSB for unlocked PIIs on the right board.

You can even go slower to fast 486 speeds, around 40 Speedsys score by forcing L1 Write-Thru cache policy on the right board, as well.

With all caches disabled, you can hit 286 territory and slow 386 speeds, too.

I once tried to disable caches and it made even dos 6.22 unusable. It became a slide show. For example when I pressed a key it took a second or two for the character that I had pressed to appear on screen in dos command line.

Baoran wrote:

j^aws wrote:

You can go 100MHz with 2x multi and 50MHz FSB for unlocked PIIs on the right board. […]
Show full quote

Baoran wrote:

I thought lowest multiplier you can go with pentium II is 2x. At least I couldn't go below 133Mhz.

You can go 100MHz with 2x multi and 50MHz FSB for unlocked PIIs on the right board.

You can even go slower to fast 486 speeds, around 40 Speedsys score by forcing L1 Write-Thru cache policy on the right board, as well.

With all caches disabled, you can hit 286 territory and slow 386 speeds, too.

I once tried to disable caches and it made even dos 6.22 unusable. It became a slide show. For example when I pressed a key it took a second or two for the character that I had pressed to appear on screen in dos command line.

That doesn't seem right. You can have slow systems with responsive key inputs still.

Then I don't understand what was going on with that system then. The unresponsiveness was the reason why I thought it was pointless to try to slow down pentium II by disabling caches. It worked normally when caches were enabled.

Highest clock rate, 133 FSB = more FPS

If we're talking about unlocked Pentium II, then it's a moot point. Even vanilla Pentium II 233 can work at 150mhz FSB with 2x multiplier, although it won't gain any significant benefit compared to 3x on 100mhz.

Why not get a 1GHz + 100 MHz Slot 1 Pentium-III

These CPUs are horrible for universal retro rig, just as Celeron Tualatin.