OC Amd 400+ Help Please!

Nineteen · May 29, 2011, 12:03 AM

Hi,

I recently upgraded my graphics card from an ati x1900 XT to a XFX ati 4850 HD. The problem is I think my CPU is holding my gpu back. I have no previous experience with CPU oc, and I noticed that people in this forum are quite knowledgeable in that regard so here I am! I would appreciate it if someone would guide me through the process by giving me sample values.

I'm posting my computer specs and uploading screenshots of my CPU-Z hardware info:

2 gigs of ram
http://imageshack.us/f/854/specsz.jpg/
by the way, the screenshot also has my idle computer temperatures
(from SpeedFan)

If there is anything else you need to know, please ask.

blibbax · May 29, 2011, 11:57 AM

Basically, all of the speeds in your computer are linked by multipliers to the bus speed (200MHZ).

Most of these multipliers can be changed, but the CPU frequency multiplier is already at its maximum value, so in order to increase the CPU speed you have to increase the bus speed.

Of course, this will increase the speeds of everything else as well, and for the most part you don't want to do that, as they will (unlike the CPU) already be close to their maximums. So you can lock the pci-e clock multiplier and drop the RAM multiplier down a notch - so that at stock speeds your RAM runs slower than it is doing currently.

You can then start to increase the bus speed in small increments - say 5MHZ at a time. After each increment, test stability in Prime95 while monitoring temperatures. I don't know what the maximum safe temperature for that CPU is, but you can have a look around on google for that.

If, after say 10 minutes of Prime95 the PC has not failed Prime95, crashed or overheated, you can move up to the next increment. If the PC fails Prime95 or crashes but does not overheat, try stepping up the CPU voltage by a tiny amount (say 0.02) then repeating that increment again. If your PC overheats, quit Prime95 immediately - you've gone too far, and should go back to the last stable increment. That's your maximum stable OC.

If you get far enough that your RAM gets back up to its stock speeds, you will need to reduce the multiplier again.

If your PC fails to post, reset the CMOS to return everything to stock.

Good luck

May 29, 2011, 12:03 AM	#1
Nineteen HardwareHeaven Newbie Join Date: May 2011 Posts: 1 Rep Power: 0	OC Amd 400+ Help Please! Hi, I recently upgraded my graphics card from an ati x1900 XT to a XFX ati 4850 HD. The problem is I think my CPU is holding my gpu back. I have no previous experience with CPU oc, and I noticed that people in this forum are quite knowledgeable in that regard so here I am! I would appreciate it if someone would guide me through the process by giving me sample values. I'm posting my computer specs and uploading screenshots of my CPU-Z hardware info: 2 gigs of ram http://imageshack.us/f/854/specsz.jpg/ by the way, the screenshot also has my idle computer temperatures (from SpeedFan) If there is anything else you need to know, please ask.

May 29, 2011, 11:57 AM	#2
blibbax What does this do? Join Date: Sep 2008 Location: Oxford, UK Posts: 4,262 Rep Power: 254 System Specs	Re: OC Amd 400+ Help Please! Basically, all of the speeds in your computer are linked by multipliers to the bus speed (200MHZ). Most of these multipliers can be changed, but the CPU frequency multiplier is already at its maximum value, so in order to increase the CPU speed you have to increase the bus speed. Of course, this will increase the speeds of everything else as well, and for the most part you don't want to do that, as they will (unlike the CPU) already be close to their maximums. So you can lock the pci-e clock multiplier and drop the RAM multiplier down a notch - so that at stock speeds your RAM runs slower than it is doing currently. You can then start to increase the bus speed in small increments - say 5MHZ at a time. After each increment, test stability in Prime95 while monitoring temperatures. I don't know what the maximum safe temperature for that CPU is, but you can have a look around on google for that. If, after say 10 minutes of Prime95 the PC has not failed Prime95, crashed or overheated, you can move up to the next increment. If the PC fails Prime95 or crashes but does not overheat, try stepping up the CPU voltage by a tiny amount (say 0.02) then repeating that increment again. If your PC overheats, quit Prime95 immediately - you've gone too far, and should go back to the last stable increment. That's your maximum stable OC. If you get far enough that your RAM gets back up to its stock speeds, you will need to reduce the multiplier again. If your PC fails to post, reset the CMOS to return everything to stock. Good luck __________________ Donate the spare computing power of your PC to help to cure Alzheimer's, ALS, Huntington's, Parkinson's disease and cancer: Fold for HH!