Weird? overclocking problem - E7200 core 2 duo

[rushholme]

I've just replaced my noisy CPU cooler with a nice new Akasa 967 and thought I'd have another go at overclocking my E7200.

I've got a EG31M gigabyte budget board (with overclocking bios)

• 4GB DDR2-800 5-5-5-15
• GTX 260 (stock) / Onboard GMA GFX
• 3 x Drives
• Antec Earthwatts 500 and Z-power 650 PSUs

I have set memory to relaxed timings and tested with both PSUs, with and without the GFX card.

My E7200 has a VID of 1.25 (very high)

At 1.4V it will do 3300mhz
At 1.5V it will NOT do 3400mhz

The temperature stays well under 60C.

I have tried different combinations of multipliers and FSB speeds, but nothing makes any difference.

Prime95 crashes out after <1min at the higher frequency.

Why have I reached this wall? It seems very arbitrary and sudden...

N.B. CPU voltage measurements are actual and include 0.3V V-droop

[watercooled]

You've probably hit the limits of the motherboard TBH - it might not be a good overclocker.

[Singh400]

Just sounds like a wall mate. But probably worthing googling to see what settings other people are using.

N.B. CPU voltage measurements are actual and include 0.3V V-droop

IIRC enable something called Load Line Calibration.

[rushholme]

I didn't think it was the motherboard as I can do 366mhz x 9
but not 3.66mhz x 9.5

What is the reason for "the wall"? not heat, not voltage, not RAM...

[Infinite]

Probably motherboard tbh, the G31 was never designed to be used for OCing in the first place.

[Terbinator]

Yep, seems the motherboard is holding you back - in comparison the P45's are known to willingly accept 450Mhz base frequencies.

[rushholme]

So what exactly is the problem on the motherboard? I am realise I shouldn't expect much on a G31 but I am curious as to what is going on. All I am doing is upping the multiplier by 0.5.

The FSB and RAM remain unchanged. Obviously the cpu voltage has been increased, but nothing else. Cooling is sufficient.

The board can handle FSBs to 400+ anyway - so what is letting it down? Is there some kind of artificial limit in the board or CPU.

Voltage in CPU-Z doesn't fluctuate from 1.49V at max load but prime95 won't even make a minute.

Its clearly a crap E7200 and I want to understand why. Thanks

[Terbinator]

Voltage in CPU-Z doesn't fluctuate from 1.49V at max load but prime95 won't even make a minute.

Its clearly a crap E7200 and I want to understand why. Thanks

Well i'd say its clearly a kack motherboard if your putting in shy of 1.5v and not getting past your desired speed. The G series isnt designed for overclocking and thus the boards logic/hardware wont support it to the lenghts as much as a high end enthusiast one would (P45/x38/x48). I dont work for Intel/or your motherboards manufacturer so i cant say if its been artificially crippled but these boards are designed for the mainstream/low end market and therefore run that way.

Im running my Q6600 on a P45 motherboard yet im hitting 3Ghz (600Mhz OC) stable on stock 1.285v, if you were to get a P45 (or similair) motherboard your E7200 should be able to hit 4Ghz or there abouts with no more than 1.35v, maybe even less.

[rushholme]

Well I did buy the E7200 2nd hand for well under RRP.

I guess that the seller couldn't clock it high either. As I said earlier, it has the highes possible stock VID for an E7200.

[watercooled]

I'm still gonna stick by what I said - it's most probably the motherboard. Just because it's not getting too hot etc doesn't mean it could go higher it's just like a CPU - you can provide excellent cooling, stable/higher voltages but there's still going to be a limit to how high it clocks. Just one more reason is maybe the VRM circuitry isn't providing a clean enough output for the CPU at higher voltages - that's why overclocking boards have more complex VRM circuitry. The G31 is, as you say, a budget board and not really intended for anything beyond a small overclock. The only way to know if you have a bad CPU is to try it in a high-end board.

[rushholme]

Just one more reason is maybe the VRM circuitry isn't providing a clean enough output for the CPU at higher voltages - that's why overclocking boards have more complex VRM circuitry.

Cheers Watercooled - that explanation makes sense.