Newbie overclocker here HELP! --> XP 2500+

Ok I am getting my new computer within the next 3 days (its custom) and have a few questions.

-I was wondering what speeds I could push my AMD Athlon 2500+ barton to. It will have the stock fan that comes with the processor.

-What is the temperature I would want to keep it under using my stock heatsink and fan.

-What is the default core voltage for the 2500+ barton?

I dont really want to change the voltage, I am not an electrician and well...can changing the voltage hurt your processor if you change it to high?

So I guess the better question to ask is what speed should I aim for with a stock heatsink and fan using default voltage?


I know you cannot give me a number but....I have herd people overclocking it 2.1-2.4Ghz with a SLK-800 and smart fan 2 whitch I will be getting soon.
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EDIT:

My system specs are:
-350WATT power supply
-ASUS A7N8X Deluxe (not sure what revision, will check when I get system)
-AMD Athlon 2500+ Barton Core
-512MB PC2700 DDR Kingston
-80GB Western Digital 8MB Buffer
-MSI GeForce 4 TI4200 8X AGP 128MB DDR

one more thing........what exactly is PR? (performance rating)

prob 2.2-2.3 is good speed to push a barton too..

its generally not recommended to use teh stock cooler for OCing so if i were you take care and excercise percaution.. esp if you're gonna use the thermal pad under the heatsink..

default voltage is 1.65v

PR rating is the rating amd gives to compare to a P4 system..
basically a barton is rated 2500+ but its actual core speed is 1.83 ghz..

as for the OCing.. i would hold off till you get that slk.. it makes all the difference in the world.. so just wait its not gonna kill you to run stock for a couple of weeks till the slk comes in