P5k SE/EPU Overclocking

[gcenglish]

After recently upgrading some components I'm keen to try and OC my system further.

I have done plenty of reading, but any advice on how to proceed would be appreciated.


Intel Core 2 Duo E8400 @ 3.00GHz

RAM 4.0GB Dual-Channel DDR2 @ 533MHz (5-5-5-15) (upgrade)

Motherboard ASUSTeK Computer INC. P5K SE/EPU (LGA775)

Graphics ATI Radeon HD 4800 Series

Samsung Spinpoint F1 1TB (upgrade)

PSU - Antec HCG 520W (upgrade)

Arctic Freezer Pro 13 (upgrade)


Currently running @ 3.4Ghz stable (9x 400, 9 being top multiplier on board)

VCore and VDimm have been left at auto. From reading forums I have disabled many settings in bios the help with OC.

Do i need to set my voltages first before trying to raise the FSB or should I slowly raise until no longer posting then raise voltages to stabilize?

Any help greatly received.

 

[jsc]

Set the RAM voltage to 2.2 volts. Set your RAM clock multiplier to 2.0. Your RAM clock should be twice the FSB freq. (I am unfamiliar with the Asus BIOS so I cannot tell you how to do this.)

Take your CPU voltage off Auto and remember where it is set. Each CPU may be a little different. The goal is to raise the FSB freq until testing (Prime95 is popular) indicates a failure. Then you increase the CPU voltage and test again.

Repeat until you reach your goal, the CPU core voltage reaches 1.45 volts, or your load temps reach 70 C as measured with something like CoreTemp or RealTemp.

The limiting factor may be CPU, RAM, or motherboard.

Our generic OC guide:
http://www.tomshardware.com/forum/259899-29-core-overclocking-guide

 

[gcenglish]

Motherboard has FSB of 1600.

So at the moment i have a multiplier of 9 x 400 FSB with FSB strap 333Mhz.

If I raise any higher it also raises the FSB over 1600. Could this be causing Prime95 errors or is it more likely to be Vcore or RAM issues?

 

[gcenglish]

I also have had initial stable results with the following:

Config #1

CPU rato x8
FSB Strap 400MHz
FSB Freq 450
PCIE Freq 100
DRAM Freq 900MHz (auto set via FSB) (have 1066 rated Hyperx)
DRAM Control 2N
Timings 5-5-5-15
Transaction Booster Enabled - Boost Level 2
CPU voltage 1.35
CPU GTL Voltage Reference 0.63x
DRAM Voltage 2.2V
Clock over charge 1.00v
CPU Spread Spectrum Disabled
PCIE ... Disabled

Config #2

CPU rato x9
FSB Strap 333MHz
FSB Freq 400
PCIE Freq 100
DRAM Freq 961MHz (auto set via FSB) (have 1066 rated Hyperx)
DRAM Control 2N
Timings 5-5-5-15
Transaction Booster Enabled - Boost Level 2
CPU voltage 1.35
CPU GTL Voltage Reference 0.63x
DRAM Voltage 2.2V
Clock over charge 1.00v
CPU Spread Spectrum Disabled
PCIE .... Disabled

Both running stable in Prime95 but need longer testing

Just wondering which would be a better set up and why also? Highest clock at lowest voltages?

Keen to try up the CPU but not sure if 1600 rated FSB on the board is a limiter.

Thanks

 

[gcenglish]

Set the RAM voltage to 2.2 volts. Set your RAM clock multiplier to 2.0. Your RAM clock should be twice the FSB freq. (I am unfamiliar with the Asus BIOS so I cannot tell you how to do this.)

Take your CPU voltage off Auto and remember where it is set. Each CPU may be a little different. The goal is to raise the FSB freq until testing (Prime95 is popular) indicates a failure. Then you increase the CPU voltage and test again.

Repeat until you reach your goal, the CPU core voltage reaches 1.45 volts, or your load temps reach 70 C as measured with something like CoreTemp or RealTemp.

The limiting factor may be CPU, RAM, or motherboard.

Our generic OC guide:
http://www.tomshardware.com/forum/259899-29-core-overclocking-guide

Thanks, very helpful. Well written article and good advice.

 

[gcenglish]

Stable @ 3.8GHz Voltage seems to be inline with forums i've read online but not ideal. No heat issues with new CPU heatsink installed last week so all good. Vcore set to 1.4125v to be stable in Prime95.

Full load temps for both cores between 55 and 60. Sounding ok?

No setting on my board for NB voltage. Also I have four sticks of RAM which apparently can require more juice.

 

[calinkula]

I have almost the exact same setup, but using an E8200 instead of an E8400. I've been running it with a 450 FSB for about 3 years now and it's still stable. So I would expect you're setup to be good in that config.

1.4125 Vcore @ 3.8 seems a little high to me since I'm @ 3.6 with 1.3125 Vcore, but it's not unreasonable. Although I have one weak core and can't get Prime 95 stable at any higher clock no matter how much Vcore I throw at the thing.

 

[gcenglish]

I have almost the exact same setup, but using an E8200 instead of an E8400. I've been running it with a 450 FSB for about 3 years now and it's still stable. So I would expect you're setup to be good in that config.

1.4125 Vcore @ 3.8 seems a little high to me since I'm @ 3.6 with 1.3125 Vcore, but it's not unreasonable. Although I have one weak core and can't get Prime 95 stable at any higher clock no matter how much Vcore I throw at the thing.

I'd be happy with 3.6 at low V's. I think from what I've just read online that i was using a multiplier rather than running FSB 1:1.

I was able to get 3.8 which I thought as stable but picked up errors overnight. To get stable around 3.7 I was running 1.45 volts which seems a bit high for the OC.

Changed FSB strap from 333 to 400 to try 1:1 (which I think it does) so I can try highest OC without RAM being a factor.

*Did memtest with RAM and no problems there. Just butchering my settings i think.

So far so good with 9 x 400 with FSB strap @ 400.