I have a compaq workstation 440bx AP200 board that has virtually no bios options. It supports coppermine PIIIs but only at 100mhz fsb.
I have a box of 1ghz 133fsb slot1 PIIIs from work that was thrown away and when I installed any of them in the compaq it will not post.
It seems rather easy to cover pins and force 100mhz fsb PIIIs to 133fsb but I can't find a way to force a 133fsb to 100mhz.
There's two main kinds of Slot1 P-IIIs: Katmai core (2.0V) and Coppermine core (1.65V). Slot1 PIII-1000 is definely Coppermine. It seems that your BIOS or mainboard VRM does not support it. Even if it's 133 by default it will run at lower speed on 100MHz FSB.
Although it was new to me when I realized that Katmai cannot run on 66 fsb on my dell gx1 - I've tested several P-IIs and P-IIIs and only P-IIs are "switchable" to lower speed.
Try to look for BIOS for your motherboard, and in fact may be not for latest - they could block officially unsupported CPU in later ones.
It runs a coppermine 700mhz cpu so the VRM and bios support coppermines. It just won't boot any cpu with a 133fsb.
According to the PIII spec sheets, on 133FSB chips, both BSEL0(pin B21) and BSEL1(pin a14) are pulled up to 3.3v.
On 100mhz FSB the cpu has BSEL0 pulled up and BSEL1 connected to ground.
I connected pin B21 to ground but still no boot. Seems there is more to it, or maybe the motherboard end needs to be modified.
I also have a MS6183(Slot1 i810 chipset), this also does not boot with 133fsb cpus. Interestingly it has a jumper to force 100fsb and when enabled the 1ghz piii will boot at 750mhz (7.5x100). I think it shows it is possible to force 440bx boards to boot these chips at 100mhz fsb.
try covering BSEL0
Depending on the mobo it may or may not work even by covering the appropriate pins. I have a Siemens OEM that won't run any 133mhz PIII no matter what you do. So annoying.
