Trying P2B-D Upgrade - Now I Giga-Hurts!

[thenige]

History:

For almost 2 years had an ASUS P2B-D board (bios build 1012b) running dual 333 PPGA celerons overclocked to 415 using the hand-modified MSI 6905 V1.0 converter cards. No problems. Had the mb jumpers set to 5X (locked anyway) and 83 bus speed to get the 415. System had 128Mb PC100 memory and a decent quality Banshee 16Mb PCI video card.

Bright Idea:

Now that mid-range celerons have dropped in price, I picked up 2 two 500Mhz celeries pretty cheaply, with enough $ to buy an ATI Rage128 AGP video card.

Installed:

All at once, I slapped in the new ATI card, threw in another 32mb of memory (also PC100), and moved the board jumpers to 7.5X at the 66Mhz bus speed to get the 500Mhz (495) settings. The jumper on the MSI6905 card is OPEN (100Mhz FSB).

Less-than-bright results:

Well I must confess that first I didn't change the bus speed from 83 (thinking the 500 celery ran at 5X also) and booted up with a single processor running at 624Mhz. That deserved more research and I found out that the 500Mhz runs at 7.5X. I trust my source that this is correct?

After fixing the jumpers to 7.5X and 66, the PC will not fire up the video display when it boots... and must be shut down hard. Basically dies after all power comes on and it enters POST. Of course I'm guessing cuzz I can't SEE anything.

My best guess is that either:
a) RAM isn't fast enough (32mb addition screwing up at 500Mhz?)
b) AGP bus speed is mucking up with 500Mhz CPUs
c) 500Mhz won't work with this board (although others apparently have)
d) <insert abuse here>

Can anyone help out ? Many thanks for all responses.

Regards,

Nigel

 

[Placid]

7.5 is the correct setting.
Try resetting the cmos with the jumper to clear it.
Power cord unplugged.

 

[thenige]

Problem Resolved - Diagrammatic Challenges

Thanks for the advise.

I ended up getting it to run at 500Mhz each when I reviewed the jumper settings as per the motherboard manual. I had the manual when I purchased the new board, however it did not show settings for CPUs above 450Mhz. So I downloaded the jumper settings from the ASUS website.

It appeared that the downloaded page was the MIRROR of the page in the manual. I just juxtaposed the settings for 500Mhz (66Mhz X7.5) from the downloaded page and the old girl boots and runs just fine!

The reason it worked OK before was that I was running 333s at 83Mhz. 83Mhz jumpers are 1-2, 2-3, 1-2. If this is juxtaposed it still works... 66Mhz does not.

Thanks again!

Nigel