Did i reach my limit?

[ziplocpicker]

I just started using Zebo's excellent OC guide today and I've found that i can't OC my mobile A64 3000+ Clawhammer's FSB to more than 235. I've tried increasing vcore to 1.65v and i still can't raise the FSB anymore.

Now, i'm happy with this OC, esp since its my first time, but I've heard of people who can reach FSBs of at least 250 and i'm wondering whats holding my system back. If i try to raise the FSB to 240, i can't even POST, but the entire system is stable under 235 MHz. I thought it would be more gradual change, ie, i would first lose stability when running Prime95, then i would fail to boot into windows, then i would fail to POST.

Edit: I'm running off an Asus K8N mobo and 2x512 sticks of Corsair valueram, not OC'ed

 

[dug777]

are you running a divider on that RAM?

If you are running 1:1 then the valueram is probably holding you back...

 

[theMan]

pci lock? but definately set the ddr333 divider.

 

[ziplocpicker]

yeah, it's set to ddr333. Whats a pci lock?

 

[Vegitto]

Ah, so that's your problem. A PCI lock locks the PCI frequency. If you don't do that, your PCI freq. will overclock with your FSB, and we don't want that.

 

[ziplocpicker]

how do i enable that? I've looked in the bios and in the mobo manual and i can't find it.

 

[Icopoli]

what motherboard do you have, odds are that's the problem.

 

[ziplocpicker]

asus k8n (non-deluxe, non-e

 

[ziplocpicker]

bump

 

[sangyup81]

he's running an nForce3

your PCI is locked, however your SATA ports 1 and 2 aren't locked
use another SATA port ike 3 or 4

also run your RAM at DDR200 so your can find your max CPU first (you want to do one thing at a time dude)

 

[ziplocpicker]

The mobo only has 2 physical SATA ports. Do I change that in the bios somewhere?

I followed Zebo's guide when i OC'd, so i had everything (cpu multi, ram divider, etc, at very low settings)

 

[Budman]

try by setting your ram speed to very low (133mhz) and lower your HT multiplier to 3X,this way those 2 things will be eliminated from the equation and you can truely see if it's the max your cpu will go to.

 

[ceasar88]

Do you have vcore adjustment option in your K8N bios? What is the version number of your bios? I've just got a K8N also but could not find anywhere to adjust vcore or multiplier...