OC on i5-750 on Asus P7P55D-E Pro

[phobiarg]

I have a rig that I am trying to squeeze a little more power from to tide me over until I can afford to buy a new one. I have always ran my computers at stock or bios preset overclocks. I have recently started experimenting with actually trying to overclock my system for performance.

My current setup is:
i5-750
Asus P7P55D-E Pro
Coolermaster Hyper 212 Plus with OEM push fan
Artic Silver 5 Thermal Compound
GeIL Evo Corsa 1600MHz 1.5V
GIGABYTE GV-R585OC-1GD Radeon HD 5850 (Cypress Pro) 1GB
Antec EarthWatts EA750 750W

My case is definitely adequately cooled but I can't seem to get reasonable temps. I started with a 4.0ghz clock I found online that seems stable, but as soon as I started testing with prime95 my temps shot up to 85c after about a minute. I canceled that test and started to downclock. I ended up with a stable setup as follows:

Core Speed 3601MHz
DRAM Freqency 514.5MHz
FSB : DRAM 2:6

BCLK 171.5
Multiplier x21.0
QPI Link 3086MHz

vCore 1.3125V
IMC 1.1625V
PCH 1.10V
PLL 1.90V
RAM 1.65V

I tested it with prime95 for 10 hours and had no stability issues at temps of ~70C CPU, 70,69,62,68 core temps.

I am just looking for advice on any changes or concerns I should consider. I would love to hit the 4.0GHz holy grail but I don't think I will be able to on this cooler.

 

[bmwbaxter]

maybe turn pll down a bit. 1.9 seems a tad high. what is it stock?

 

[phobiarg]

I dropped PLL to 1.85, seems to be ok, temps look to be the same, stock is 1.8, I tried 1.8 and it hardlocked and required a CMOS reset.

 

[bmwbaxter]

I think temps are going to be the limiting factor, since everything else seems to be solid.

 

[redduc900]

A Vcore of 1.3125V seems awfully high for only a 3.6GHz clock, unless you have Turbo enabled. I think more along the lines of 1.20-1.25V would be sufficient. Depending on how much RAM you have installed and the current DRAM frequency, you nay need to bump IMC voltage to approx. 1.20V or slightly higher.