Would I benefit much from getting a new motherboard and overclocking

if your going to get a new motherboard you may aswell upgrade the whole lot. Also, just because the vcore voltage is locked doesnt mean you cant increase the FSB. Those CPU's are known for sometimes hitting 3 ghz without voltage increase

I know what your saying but I dont have that kind of money at the minute was just wondering would it be worth doing and would I get much of a gain in games like BF3 which I plan on buying as soon as it comes out.

I have tried to overclock many times and it failed every prime95 test even with the slightest overclock, the motherbaord is an "Asrock-4core-FullHD" which I believe is just not up to the task.

^I dont believe its your motherboard. Have you updated the board to the newest BIOS? do that if you havn't. I just dont believe that you cant increase Vcore, im pretty sure the board is capable of it. There must be something else going on.

I have the latest bios which is from 2008, I also looked endlessly online for a way to manually increase the vcore and couldn't find anything.

Im not sure what else could cause the OC to fail if all I was doing was increasing the FSB, surely that only affects the CPU.

I might give it another go tonight when I get in from work and ill post the results here, it was ages ago when i first tried but i do remember it failing every single Prime95 test.

Ok so I just tried to overclock:

increased the FSb to 300x9 =2700

ran Prime95 and it failed the large-FFt's test after 8 minutes so I rebooted set the NBcore to 1.4v and the Dram to 2.1v. booted up and it failed the same test but lasted longer,

I then ran the Small-FFt's test for over an hour without fail, next I tried the blend test which it failed after 15 minutes.

I read on another forum that if the OC fails the Large-FFts and Blend test but pass's the Small-FFt's test it is more likely a ram / northbridge problem.

Any Ideas ?

lower your ram speeds

Ok so I had another go last night, went into the bios and these are the options I have enabled etc:

OC mode: CPU, PCIE Async
CPU freq: 300
Spread spectrum: Auto
Intel Virtualization tech: Enabled
CPU Thermal Throttling: Enabled
Intel Speedstep: Auto

You mention turning down my ram speeds but the interesting thing is I checked the dram frequency last night after the second OC attempt failed and it was set to Auto and in brackets beside it it said 333mhz (DDRII 666mhz).

so i took it off auto and set it to 400mhz (DDRII 800). There was also an option called "Flexibility option" which was disabled so i enabled it, I then rebooted and ran prime95 and it was running the Large-FFTs test for over an hour and a half with no problems and temps on the cores never went above 55c.

Do you think my overclock is now stable and I can increase the FSB more and run the test again or is 1hour and a half not long enough in prime95 and I should run it for longer at the current overclock ??.

Also do I need to run and pass all three of the available Prime95 tests to ensure that the overclock is stable or just 1 of them ?.

Thanks for the help!

If you want to overclock your chip but not spend alot on a new board I suggest you buy a Gigabyte or Asus G41 Mobo, they're dirt cheap OC well and I've run my Gigabyte G31 OC'ed for 4 years now and it's still reliable, OC'ing your chip to 3.4 or 3.6 would benefit you alot so go for it.

Here's your major problem. What few P43/P45 motherboards there are now use DDR3 RAM. DDR3 RAM is pretty cheap right now.

Second problem - G41 boards are pretty cheap - about $50. They only have two RAM sockets. Total cost about $80. Using a P43 or P45 board, your cost will be around $150.

Third problem, using the G41 board, while a cheap solution, will limit your overclocking potential. The G41 is an economy chipset with a limited upper FSB freq limit of about 350 MHz. That means a realistic limit with a Q6600 is about 3.2 GHz.

Upper limit of the Q6600 is about 3.4 - 3.6 GHz. Upper limit of a Q6600 with the stock heatsink is about 3.0 GHz. So better than stock cooling will add another $30 minimum to the budget.

If you can get your system up to around 3.0 GHz, I do not think that trying to go higher is worth the expense.

Right now, I have 6 Core2 systems, all G'byte - two P45's and a P35 in a home network, and three G41's doing office automation tasks.

yea I see what you are saying, thanks for the help. I am going to try and push it to 3.0GHz when I get home and test its stability. If i can get it to 3.0 i will be really happy with that. I already have an aftermarket cooler so that shoul help keep temps down.

Just trying to push as much performance as possible out of it so that BF3 runs as good as it can when I buy it this weekend. If I can get it to 3.0 and its stable how much FPS gain do you think I will achieve ? as I know that BF3 is very CPU intensive.

I have my G31 running a q6600 stably @ 3.3Ghz I have just a small niggle I'm working on and it should get to 3.4 or 3.6Ghz so a cheapy board could definitely work with a bit of luck, go Gigabyte you won't be sorry.