AMD 1800+ and Abit KR7A-Raid

polkmaniac

Distinguished
Jan 3, 2003
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I'm not familiar with the overclocking process and what settings do what. Can someone explain how to overclock my CPU. I have an AMD 1800+ and an Abit KR7A-Raid board. Basically I'm just looking for a way to make things run a little faster.

I am computer literate, just need this piece cleared up.

Also, is there anyone out there who know if I can put the 2400 on this board. The latest BIOS from Abit only mentions the 2200 with the T-Bred core, wondering if the 2400 will work.

Thanks
 

svol

Champion
I think the XP2400+ will work.

Anyway about overclocking:
The CPU speed is determined by the following formula: multiplier*FSB=CPU speed.
Your CPU is factory unlocked, so you have to unlock him first (closing all L1 bridges as shown in THG Video 3) if you want to use the multiplier to overclock. Your default muliplier is 11.5
But you can also increase the FSB (default 133MHz (266 MHz DDR) to overclock your CPU. But this will also overclock your memory (with your motherboard memory speed=FSB) so if you have low quality memory you wont be able to reach a high OC by FSB.
Increasing the FSB also increases your PCI and AGP bus clocks as they are determined from the FSB (PCI is 1/4 of FSB:133/4=33 and AGP is 1/2 of FSB:133/2=66)... modern viedeocards (GeForce2 or higher) can run at really high AGP speeds up to 80-90MHz without any problem, so your videocard wont hold you back. But PCI most PCI cards can only handle a PCI speed of 40MHz (thus a FSB of 160MHz) and cheap PCI cards are even worse overclockers.

What you can do is start increasing the FSB a couple of MHz a time and see if it POSTs (=BIOS loads) at the higher speed. After increasing it with about 5MHz you can boot up your OS and run some benachmarks (like 3DMark2001SE, SiSoft Sandra) to see if everything runs stable. Always keep an eye on the temps! If it doesn't run stable and your temps arent high you can increase the VCore a little bit from 1.75V to 1.8V or even 1.85V if you have good aircooling. Increasing the VCore can help your CPU run stable at higher speed, but keep in mind that a higher VCore always means higher temps.
If you don't have very high quality memory and after OC'ing a bit the PC isn't stable you can download the program Memtest86 from <A HREF="http://www.memtest86.com" target="_new">http://www.memtest86.com</A> and check if your memory can handle the higher speed. If it generates lots of errors in the Memtest you have to lower your RAM timing (ie from CAS2 to 2.5) and increasing the Vdimm with 0.1-0.2V can also help.

My PC eats so much money that I'm in 'desperate' need of it to buy PC3500 RAM, help Svol with his OC project!
--- PM me for information.