An anomalous overclock benchmark?

[Hotspot]

Hi all,

In the slow process of learning to overclock via the bios in a modest way I am using an E8400 and initially raising the FSB in small steps with stability tests after each adjustment. Tests used are Prime95, Everest Ultimate, Intel Burn and a benchmark tool called "Userbench Encode 2009" which gives a quick and easy number to assess progress.

The general expectation has been for every five I raise the FSB the bench mark improves by about two, as has been the case until I upped the FSB from 345 to 350 (like I said, this is a modest exercise), expecting a benchmark of about 46 up from 44. However, the benchmark jumped to an unexpected 58.

This was reflected in the performance of FSX between the overclock to 350 and running the benchmark (to see what was occurring ), as FSX was supremely smooth - unusual for an E8400 at only 3.15 mhz (normally 3.00)

My question is how 'normal' is it to get sudden leaps in performance like this when overclocking? 

[Hugh Johnston]

I over clocked my E8400 to 3.6 easily. You should be able to do the same. I just had to change the FSB to 400 and set my voltage to a set amount(I forget what amount) and take it off auto voltage.

I noticed a massive performance increase. I don't know why I didn't do it sooner.

Your risk though

[jnrjim67]

No thats not normal, to go from say like you say 44 to 58FPS thats like a 25% increase not possibe with sush a small O/C to get such a jump your CPU would have to be running about 4Ghz for that difference and those E8400's can do 4Ghz relatively easy with a high end CPU cooler. Not sure why you got those results but its not possible with such a small overclock for such a big increase.

[mattn79]

I found the sweet spot with my E8400 on air to be 3.8ghz with a Noctua NU-12P cooler. It can run at 4gz but the temps according to Real Temp sit around 60c or just over at full load, as where with 3.8 it sits about 56-58c which is a bit more comfortable.

[Hotspot]

Thanks for the info fellas, will advise progress - hope to get to 3.8 - I had an E8600 at 3.969 using the gigabyte EzyTune and 8Gb ram, but when I changed it to four gigabytes of Ram to pass the computer on to my son it crashed - so I'm trying to learn a bit not using oclock programs on a different comp.

I'm using an Th'right U120E cooler and five extra 120mm fans, plus a three 95mm fan a/m cooler on the graphics, two 40mm fans on the ram and an 80mm fan fitted under the motherboard beneath the CPU, so hoping it doesn't need liquid cooling - fingers crossed. 

[Hugh Johnston]

I found the sweet spot with my E8400 on air to be 3.8ghz with a Noctua NU-12P cooler. It can run at 4gz but the temps according to Real Temp sit around 60c or just over at full load, as where with 3.8 it sits about 56-58c which is a bit more comfortable.

G'day Matt.

What were your voltage settings? Mine just couldn't hold a clock at 3.8 but have read somewhere that having an external hard drive plugged in may be the issue.

[mattn79]

Here are my voltages for each of the clocks - 3.6@1.225v, 3.8@1.237v or 4.0@1.281v.

Each clock was stable running Prime 95 for 12 hours, as I mentioned above I settled for 3.8 as there wasnt a big difference between 3.8 and 4.0ghz and it ran a bit hotter you can see it needed a big jump in volts to be stable at 4.0.

M/board is a Gigabyte EP45-DS3L and memory is Geil DDR2-6400 locked at FSB:DRAM 1:1

I'm happy with everything other than the video card really (ATI 4870 512mb). Have considered selling this vid card and getting a 275 or 285GTX but not 100% sure, maybe I'll wait til the new Nvidia cards are out next year.