Basic AMD2500+ o/clocking

[Steve B]

Can one of you GURUS give me some pointers about gettin' this chip cranking?

I see lots of "o/c to 3200" ... how do you do it, and safely?

ie FSB freq, voltage settings etc.


Hang Loose

 

[Masque]

Steve, please read THIS first.

 

[Steve B]

Point taken.

Thanks for the CONSTUCTIVE advice, unlike some others...

 

[Arris]

If you have good cooling on your CPU then you can try running a higher multiplier. The real overclocking beauty is going from the default fsb to a higher one to increase bandwidth to the processor. If the 2500+ is a 333fsb model then you may be able to run it at 400fsb. But this will stress your memory unless your motherboard allows you to change the ratio at which the ram runs. To run a 400fsb you will need at least PC3200 ram, to run at a 1:1 ratio, which gives best performance. Otherwise you can reduce the speed at which the memory runs by altering the ratio in the BIOS. Most nForce2 boards have what is known as a PCI/AGP lock. This is where the clock used to set the speed of the PCI and AGP bus is locked to 33Mhz and 66Mhz and is not a value worked out from the fsb speed. This means the only restrictions on overclocking the fsb are the CPU and memory. If your motherboard doesn't have this Lock feature then your overclock will be limited to increasing the CPU clock multiplier.

From memory I think the default multiplier is 11 and default fsb is 166. 11 x 166 give your the default 2500+ speed of 1.8Ghz. If you up the fsb to 200 (400DDR) then you will have 11 x 200 = 2.2Ghz. But your probably going to have to watch your CPU temperatures to make sure your cooling is sufficient to run at this speed. I would suggest first if your Barton is unlocked (i.e. allows the multiplier to be changed) and if your ram can run at 400DDR speed then drop the multiplier to 10. 10 x 200 = 2Ghz. Then monitor the CPU temps in the bios or you can use a software tool from your motherboard manufacturer if they were nice enough to supply one or download Motherboard monitor if it supports your motherboard. Monitor temperatures in both idle and loaded situations. For loaded either loop 3dmark2003 or play a game for a little while then check the temperatures again.

The Athlons operating temps are up to about 80C or something like that but I've always found that anything over 60C starts causing errors so best to try and keep your overclock to a level where your temperatures don't get over high 50s. If your cooling is sufficient you might be able to get a further overclock by increasing the voltage to the CPU core (if your motherboard has BIOS options for overvolting). But to start with I would just try increasing the multiplier for a simple overclock and watch the temperatures.

Also as a stress test and to check for errors many people use SiSoft Sandra and Prime95 to test for errors in memory when overclocking. These will allow you to double check that your apparently stable overclocked system is stable.