2500K @ 4.8GHz

I know there are plenty of these threads, but since no cpu is the other like I though I'd make one myself. (sorry )
I just recently got myself a i5 2500k coupled with an ASUS P8Z68-V PRO and some Corsair Vengence 8GB 1600MHz, 9-9-9-24 1.5v. I have this system in a Fractal Design Arc chassi using 2x140mm fans for intake and 140+120mm for exhaust. This is with a Noctua NH-D14 on the cpu.

I managed to get to 4.5GHz pretty easy with just some minor changes in the bios. I did need 1.3v to reach that, but pretty much only changing my vcore and settings for my ram. Howerver, I want to try and go higher (ofc)

After reading a bit on what settings people tend to use I ended up with these settings trying to get it stable at 4.8GHz:

AI Tweaker
Blck Frequency - 100
Turbo Ratio - By All Cores - 48 Multiplier
Internal PLL Overvoltage - enabled
Memory DDR3 1600MHz
Epu Power Saving Mode - disabled

CPU Power Management
CPU Ratio - auto
EIST - disabled
Turbo Mode - enabled

Digi+ VRM
Load-line Calibration - ultra high
VRM Frequency - Manual @ 350
Phase Control - extreme
Duty Control - extreme
CPU Current Capability - 110%
CPU Voltage - 1.4v
DIMM Voltage - 1.5v
rest on auto

Advanced tab -> CPU Config
Cpu Ratio - auto
Internal adaptive thermal minitor - enabled
All cores active
Limit CPUID Max - disabled
Execute Disable bit - disabled
Intel virtualization tech - disabled
Speed step tech - disabled
Turbo mode - enabled
CPU C1E - disabled
rest on auto


I am not sure about the format, but I hope it is somewhat readable. I managed to run Prime95 (small fft) for 10 minutes before the 4th core failed.
Now I am not really comfortable going above 1.4v, but was hoping I could tweak the other numbers to perhaps make it stable. Although 1.4v is considered a "safe 24/7" voltage right?
I have been running all these settings but with a multi of 47 and prime95 seem to go strong even after a couple of hours. So seems somewhat stable around those clock speeds.

Running at 4.8GHz with 1.4v I had a temperature of 70°c as max after 10 mins when the 4th core failed. Running at 4.7GHz with 1.4v I am seeing a max of 69°c as max. So my temperatures seem to be within reasonable bounds, no?

I guess I am pretty happy with a 4.7GHz overclock, but thought I'd make a post here to see whether or not I could possible puch it up to 4.8GHz. It being "stable" for around 10 mins show it's not too far-fetched to believe so I'd say Or perhaps I've just reached the limit of my chip. And since I am only gaming, I guess 4.5GHz with 1.3v should be aduqate as well. But if I "can" get that extra mile, why not..right?

Any help on the subject would be much appreciated!

The voltage is fine (1.4) and 70C max is still quite good (under 80C is my 100% load temp max). It looks like 4.7 is about as high as you are going to go at 1.4, the rest of your settings look good to me. If you bump up to 1.41 you could see if it can do 4.8, or you can drop to 4.7 and see if you can disable CPU PLL Overvoltage to allow you to put the PC to sleep (as CPU PLL OV prevents it from working).

I will try and see whether or not I can reach 4.8GHz stable with 1.41v. If not, as I said earlier, I am pretty happy with 4.7GHz and will settle with that. At 4.7GHz it seemed to be stable using 1.38v. Howerver I only ran prime for an hour or so. 1.37v was a bust so trying 1.375v at the moment.
Would CPU PLL Overvoltage have any other negative impact on my system by staying enabled?

Thanks for the input!

not that I am aware of, the only thing I ran into was the sleep mode issue

Ok, thank you.

You probably would hit at least 76 C with Linpack.

After running prime95 through the night I noticed it's not even stable at 4.7GHz using 1.4v. So I decided to back down to 4.6GHz using 1.37v. I tried from 1.35v, to start with, but one core kept failing after 10-30min of prime95. So I slowly worked my way up to 1.37v where I am now. I will keep looking for a 100% stable spot running at 4.6GHz and see where I end up.
I was pretty confident I would be able to get it stable at 4.7GHZ, but as I said earlier, I don't want to go over 1.4v.