[Solved] I5-2500k/GTX 460 Overclock

What program do you use to benchmark and how exactly do you know if it's stable? I used MSI Kombustor for testing my graphics and I don't know if that's the most efficient way to check if the graphics are stable.

How high could you get with 1.42V on this setup? I use my computer for heavy gaming and programming, so I don't want to push it unnecessarily. Should 4.5Ghz be enough of a boost?

You should NOT need 1.42v for 4.5Ghz, in fact it should be more like 1.32v for 4.5GHz. Anything over 1.4v can shorten the life of your CPU to a matter of months. I personally keep my 2600K under 1.35v. An H50 is not a real good cooler. It really does worse than a Hyper 212 so heat might be an issue for you. Use Prime 95 to check your CPU overclock. I would run it 4 or 5 hours at least and 8 to 10 is recommended. Also use Coretemp or Realtemp to monitor your CPU. Anything over 70C and I would start reducing voltage and clockspeed. I would guess you will get in the 4.1-4.3Ghz range with that cooler but you might get a "good" chip that runs cool and hit 4.5Ghz.


I run my GTX 460 at 820-1640-2000. I use Furmark to test stability and temps. That is on stock voltage. As stated above keep it under 90C and you will be fine.

I overclocked my CPU through BIOS and AI Suite II and set the CPU Voltage to 1.35, but when I run Prime95 and stresstest it, CPUZ shows my voltage going up to 1.45. This is beyond the limit that you guys recommended, and more importantly, beyond the voltage I have set. Is this supposed to be happening?

For some reason, I can't change my voltage in the BIOS. That's why I use AI Suite.

Furthermore, I realized that when it goes +3.3V, it automatically resets itself to a x33 multiplier so it isn't even staying overclocked. Do I need to update my BIOS? Ever since I built this computer, CPU Voltage has not been an option under my BIOS. I can change the voltage offset but not the voltage itself.

What do you mean by "when it goes to +3.3V"? +3.3V is just an output on your PSU...

You should be able to change the voltage mode (from offset to manual or fixed). You may want to flash it if your still having trouble but just be careful, flashing can be dangerous

Wow... yeah damn straight it should be reseting your settings if the voltage goes that high, 1.68V could kill your CPU!

You'll need to go to ASUS's website, look for your motherboard and download the latest BIOS, then put the BIOS on a memory stick, reboot, go to BIOS and there should be an option for EZ Flash, use EZ Flash to flash the BIOS.

Seems like other people are having similar issue's to you.
http://forums.anandtech.com/showthread.php?t=2138081

Where it says "CPU Offset Voltage" in the last screenshot, can you change that to manual, or a value like 1.35V ?

And yes enabled is fine, its different on most motherboards.

If you cannot change the voltage then contact ASUS as it'll be a BIOS issue.

Yeah its likely not a stable overclock, are you overclocking the core and mem at the same time?

If you run the benchmark again at 830/1640/2000 to you get a slightly higher score?

Yeah your voltage is fine, i'd still contact ASUS though as that isnt acceptable in my opinion (its a pretty important option!)

Are you running the benchmark whilst stress testing the CPU? your frame rate makes no sense compared to your stock score...

Try running Futuremarks 3DMark11 benchmark as you can compare your score against similar systems.

I'm really not sure what's going on with Unigine Heaven.

15% whilst idle is quite high, should be closer to 1%

wow what a prick, a quick google shows that other people are having the same issue so I would imagine its a BIOS issue, whether or not ASUS is going to do anything about it is another matter.

Cant believe there response... they make the BIOS easily accessible, generally user friendly (except Vcore option) and yet if you touch it your warranty is gone

Your 3dMark11 score is slightly better than average, try increasing the overclock slightly and re-run the benchmark.

Considering I have the latest BIOS, I doubt they'll be able to do anything about it anyway. I could continue to use AI Suite to change the Voltage myself.

As for the 3DMark11, do I keep running the test until I see the latest score drop from the previous score? I don't want to keep pestering you with little increments.

Do I ever increase the memory clock higher than 2000mhz? I'm not exactly sure what the memory clock does, or if it's worse going higher with this card.

Also thanks for all your help. You've been awesome.

Yeah by all means , you can overclock the VRAM until it becomes unstable. Video Random Access Memory stores textures used in 3D apps.
GDDR5 (Graphics Double Data Rate) is hard to overclock because when it becomes unstable you wont see artifacts, if the Vram fails to complete an instructionit will re-run the instruction until it completes it successfully, this process can decrease performance. So effectively a higher unstable VRAM overclock can be slower than stock frequency.

So just watch out for performance decrease when overclocking VRAM