Hello,

I am overclocking my CPU, therefore, I need to know the maximum vcore I can safely use. AMD's official website sucks and I am unable to find the information. My CPU is AMD Athlon 64 3200+ (default 2000 MHz,200x10) and it has 512 kb cache, E6 stepping and uses 92nm technology.

I am using vcore of 1.575 at the moment and my CPU is not stable at 2.40 GHz (240x10). My goal is 2.40 GHz right now.

Thanks for your help!

I'd say 1.575 is a little (alot) too high. I'd recommend keeping it below 1.45 volts (really below 1.4 volts stock hsf) if cooling on air. 1.575 is IMO too high for water cooled, but you'd probably be alright. I bet you're not getting to 2.4 b/c your cpu is getting too hot with that voltage and can't stay stable. try clocking it to 2.4 at 1.375 V or 1.4 v and see what happens. more voltage is only the answer if you have adequate cooling

1.45 is the safe limit 1.5 is the HARD limit

i had my venice at 1.45 volts at 2.9gHz stable with aftermarket cooling.

Couple of questions to help diagnose the problem ...

1) What are your current temperatures? (Bios temp will do)
2) What cooling do you currently have on it?
3) You've set vcore to 1.575v, but what does the hardware monitor in Bios say the CPU is actually getting?

You should easily be able to get 2.4GHz or more out of that chip, so at the moment i'm leaning towards agreeing with sepayne21 that the voltage you're feeding the chip is probably making it too hot with your current cooling for it to run stably.

1.575v is a little bit on the high side, but not as drastically as some people think. Your CPU (and one of my older ones, a 3700+ san diego core) has a default voltage need of 1.35-1.40v, and as long as you have good enough cooling it should be safe to add 0.15v to the top end of that.

More questions I just remembered...

4) What speed RAM do you have and what speed do you have it set to in Bios?
5) What link speed/HT multiplier do you have set in the Bios?
6) Which motherboard do you have?

Hi, I don't know if this information is still useful but I thought I'd share it.

I believe your Venice core should be capable of 2.4GHz..2.6GHz and beyond is not uncommon using standard air cooling.

I have the same CPU (retail), and it does 2.5GHz using 1.45v and air cooling.

I'm also assuming you're using DDR-400/PC3200 memory, but there's plenty of leeway if this isn't the case.

OK, just a quick recap on some important settings..

1) CPU core speed = base frequency x multiplier.. 200MHz x 10 = 2.0GHz

2) HT Link speed = based frequency x HT multiplier.. 200MHz x 5 = 1.0GHz (2.0GHz DDR). 2.1GHz is the safe limit.

3) Memory speed = core speed divided by memory divider (10/12/15/20):

2.0GHz / 10 = 200MHz (DDR-400)
2.0GHz / 12 = 166MHz (DDR-333)
2.0GHz / 15 = 133MHz (DDR-266)

4) If using memory in dual-channel mode, its stability can be increase by altering the 1T/2T setting to 2T.


I am confident your vCore setting isn't the problem, and that you're setting it unnecessarily high.
I think your RAM and HT link speeds are too high.


Procedure

How you alter your computer's settings will depend on what motherboard you have. You will be able to alter settings entirely in the BIOS, or have to use a combination of BIOS settings and Windows software.

Ideally you want to do as much as you can in the BIOS, but if that's not possible you still have plenty of flexibility even with the cheap boards. This was the case with my S939 Abit NF-95, and I can overclock the processor in seconds once Windows boots.

Enter the BIOS and..

1) Enter the BIOS and set your vCore to default (if applicable). Reboot.

2) Enter the BIOS again. Set your RAM speed to 166MHz (DDR-333)

3) Set the 1T/2T timing to 2T

3) Set the HT multiplier to x4

4) Increase your base frequency from 200MHz to 240MHz. If you can't do this in the BIOS you'll need to do it in Windows, using ClockGen or similar.

ClockGen and another piece of software called CrysalCPUID can confirm your settings. Crystal also allows you to adjust the vCore from within Windows, which is useful is you do not have the option to do this in the BIOS.

If all is well you should be running at the following settings:

vCore = 1.400v
Core frequency = 2.4GHz
Base frequency = 240MHz
HT link speed = 240 x 4 = 960MHz (1920 DDR)
Memory speed = 2.4GHz / 12 = 200MHz (DDR-400)


If you want your processor to operate faster than 2.4GHz I would recommend starting with a RAM speed of 133MHz.

Here's my current settings, using two sticks of cheap RAM DDR-400 memory, one of which fails at 200MHz:

vCore = 1.450v
Core frequency = 2.4GHz
Base frequency = 266MHz
HT link speed = 266 x 4 = 1064MHz (2128 DDR)
Memory speed = 2.6GHz / 12 = 178MHz (DDR-356)

Sorry if this seems like I'm throwing a lot of figures around, hopefully you should be able to get some joy with your system and whilst using lower voltages. With a good cooler and some decent RAM these systems can really fly, however I would rather aim for an AM2 system that offers cheaper dual-core upgrade options and (65nm) processors that only draw less than 20% more energy than their single-core variants.

Correction as regards my current settings:

vCore = 1.450v
Core frequency = 2.53GHz (multiplier = x9.5 using CrystalCPUID) <--------
Base frequency = 266MHz
HT link speed = 266 x 4 = 1064MHz (2128 DDR)
Memory speed = 2.6GHz / 12 = 178MHz (DDR-356)