Abit SH6 MoBo

[frantadr]

I have Abit SH6 (Intel 815E chipset) and PIII-550 (Katmai) CPU. The CPU run wery stable at 125 MHz FSB, but only at clock CPU:SDRAM:PCI ratio 3:3:1. When I set this ratio to 4:3:1 or 4:4:1, the computer don't boot. Does anyone know, what is bad?
Abit SH6
PIII-550 at 2.3 Vcore
2x128 MB SDRAM PC133
Diamond Stealth III-S540 AGP
Dimond SupraExpress 56i PRO
Crystal PCI sound card
IBM DTLA 307030 HDD
HP 7570i CD-Writer

02.20.2001:
My cooler is Alpha PAL 3125 (two 60x60x25 mm
fans). According to my opinion, the problem is in BIOS. The computer did not boot when ratio of CPU:SDRAM:PCI clock is 4:3:1 or
4:4:1 not only at 125 MHz but also at 100 MHz (CPU clock).

[marty]

You may have reached the limit of your chips ability to overclock. If so that is as high as you can boot. But if you are lucky you may get some more speed from your 550 chip.

First what type of heat sink and fan do you have for your 550?? You need more than the basic heatsink that came with your machine! I have an Alpha PAL6035. I also have the Sanyo Denki fan which is a bit slower and a lot quieter than the Delta that originally came with my PAL6035.

Second you should use some software cooling program to also keep the heat in check. Then your 550 will stay stable in Windows when the heavy duty programs kick in. You can actually see the temps rise as you use your computer more.

Where can you get a temp guage and a software cooler along with a program that will allow you to try a higher FSB?? Find the program CPUCool. It is a cooler and a temp guage and it lets you bump your FSB little by little after Windows boots. So you can boot at 125 and then move to 128 and if that is stable try 130. You actually change the FSB in Windows.

I have a similar motherboard. When I first bought it I couldn't go faster than 120 FSB. Then I changed back to the Original Intel Heat sink and I could do 125 FSB. I added the $2 Radio Shack heat transfer paste and I could do 128!! Before my Alpha PAL 6035 arrived I could do 130 with CPU Cool!

Now with the PAL 6035 I can do 133 from a cold boot and CPU Cool will let me get to 137 FSB.

Maybe some others on the board can give you more ideas. Make sure that the PAL6035 will fit your motherboard and processor before ordering it.