Is it ok to use an unsupported CPU?

[orondf]

Hi,
I have an Asus P4B533 M/B (Socket 478, 533Mhz FSB), and I'm wondering if I can use an Intel Pentium 4 2.60C(S478) with it, which has 800Mhz FSB, and my M/B supports 533Mhz.
I should be able to overclock the FSB, and use 400Mhz RAM, but the CPU isn't listed in the CPU support list on asus.com. Is it possible to use that CPU on my M/B?

 

[JMMD]

If it doesn't power on then you have your answer.

 

[B00kWyrm]

Unless I misread the information at ASUS, re: P4B533 you are covered.
At most you might need a bios update.


Per Asus:

If your motherboard BIOS version number is greater than the BIOS version listed above (1008), then you will not need to flash your BIOS. However, if your BIOS version is smaller than the version listed above (1008), then you will need to select and download the latest BIOS to update your system. We kindly remind you that there is a certain risk level involved in BIOS flashing, please refer to "BIOS Flashing Method ". If you still have doubts, we will strongly advise you to consult with a PC Professional or your PC dealer for further assistance.

 

[orondf]

There are like 3 revisions of that cpu, 2.60 is listed but not 2.60C.
I have BIOS 1015.

 

[B00kWyrm]

Well... since finding a different board for that cpu may be more difficult, I am with JMMD.
What would it hurt to try? Looks like your BIOS should already be as good as is possible.
You may need to underclock your cpu, even as you overclock the bus...
might take some experimenting to find the best settings.
Have fun.

 

[orondf]

Thanks for the help.

 

[orondf]

Swapped CPUs today, works fine. The only problem is that when I boot at 200Mhz BCLK I get beeps for no DRAM installed. Maybe the reason is that the M/B only supports timings of up to 2.5-3-3-7 and the RAM is rated for 2.5-3-3-8.
Maybe installing beta(!) BIOS 1015.003 (the newest) will solve this?

Update: Got BSOD 0x8E with 160Mhz BCLK and 2.5-3-3-7 RAM timings. Setting the timings to [By SPD] sets them to 2.5-2-2-6.
Will setting them to [By SPD] or maybe 2.5-2-2-7 fix the problem?
DRAM voltage can be set to 2.6V, 2.7V and 2.9V, RAM is rated for 2.5V. Will increasing the voltage solve this?
What should I set the timings and DRAM voltage to?