Pentium MMX Multiplier past 3.5 on 430TX? BF2 jumper work?

I have a Abit TX5 430TX motherboard and I want to be able to push a Pentium 200 MMX to 300 on it using 66 bus. It will only let me set the Pentiums up to 3.5 multiplier. A AMD K6 300 automatically brings up the higher multipliers up to 5.5 . Before I start to solder a BF2 switch to the backside of the board, will the BF2 trick bring up the higher multipliers in the BIOS for the Pentiums or does that only work for the AMD/Cyrix chips?

just set the FSB to 100? wouldnt that work better as you'd be getting more mem bandwidth too?
good luck.

Intel 430TX boards didn't come close to 100mhz. 83mhz was about as high as they got.


AFAIK, the BF2 mod works on all processors, not just AMD processors

Know Nuttin said:

Intel 430TX boards didn't come close to 100mhz. 83mhz was about as high as they got.


AFAIK, the BF2 mod works on all processors, not just AMD processors

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First of all:
1) Intel MMX chips are either multiplier locked, partially locked, or fully unlocked. My 166 MMX was unlocked.

2) The multipliers range from 2 to 3.5 (66x2=133. 50x2=100, 66x2.5=166, 66x3=200, 66x3.5=233).

3) No other pentium chips had higher multipliers until P2's. And I think the highest MP for a P2 was 5. (P2-333 was 66x5, IIRC), then 100 FSB chips became standard.

The P2-333 was actually a P2-400, but was relabled purposfully (Intel's first "remarking" job) and had a pin sense which forced its multiplier to 5 if it was run on a native 66 FSB motherboard, but the 100 FSB recognition was still on the hardware. You could either use a nail polish trick, or, Abit boards (The first board to do this) allowed a SEL# high/low signal, which would trick the processor into thinking it was on a 100 FSB board (just setting FSB 100 did NOT work, as the chip was set for 66 FSB), and causing the processor to drop its multiplier from 5 to 4, 100x4=400 mhz.).

Shuttle made a Spacewalker 430TX board with the BF2 bumper built in, but I missed the end of the auction this morning on ebay. Iv'e scoured the net but only found instances of Pentiums overclocked 3.5x83 but nothing on anything above 3.5x for the 430TX. Unfortunately there is something in my system that doesnt like the 83 bus. I'll try the BF2 trick out this week and let you know how it goes. My main rig is a Athlon M 2400+ running @ 3200+, nice and quiet. The 430TX system is for my DOS/Win95 rig.

Found a Shuttle HOT 569 with hard jumpers, but when I set then to 4, I am denied and given a 1.5. I also tried BF2 hardwiring the sockets on several boards, but no-go. As stated earlier, the CPUs I've tested are locked to 3.5 max.
I'm going to stick with my Abit TX5 for my retro DOS/Win95 system. It overclocks well at 3.5x83 if I up the voltage on the Pentium 200.

so it means your chip is locked...but even if it wasn't it wouldn't go over 3.5
anyways, why clock a Pentium MMX?

why not just buy a cheap machine in the 500~ MHZ range? your OC'ing a computer to run MS-DOS...

why not just dual boot your XP-M or find another machine of a higher power level?

This comp is just for fun, I like to tinker with older machines.
I do also have a DOS/Win98 comp with a Celeron 533A @ 800 with 2 Voodoo 2s in SLI.

uhh... sli is a new nvidia technology.....

and my best P1 oc was 83 x 3.5 on a supermicro P5mma98 rev 2 board. i miss that board, wish i still had it and the cpu. i had a stock amd cooler from a thoroughbred 2100 on the cpu, ran niiiice and cool hahaha. it was the first board to be mounted in my antec case.

P1 and old overclocking like that is fun, caus you arent worried at all about killing something. if i had motivation and parts, id go all out and do PLL mods to a P1 and try to see how high of a FSB i could get. would be great tobe pushing 150 FSB, if i could find som PC150 somewheres. be sick to have a phase cooled P1.... hahaha.....

then manage to get the AGP slot to take to a somewhat modern card... at least a ti200. it would be so much fun.

Actually 3Dfx were the first that I know of to do consumer SLI. In 1998 the 3Dfx Voodoo 2 boards became available to run in SLI via a cable much like that of a floppy cable to connect the cards. In 2001 ??? Nvidia bought out 3Dfx and and one can only guess the same technology slipped into Nvidia's new boards.

Yeah, I can get my 200 mmx up to 3.5 x 83 stable. Have to bump my voltage from 2.8 to 3.3 to get it to run. But i will run it at 200, most games from the early-mid 90s dont need more.