Overclocking my new Q9550 on an Abit IP35 Pro

[Ravynmagi]

I just got my new Q9550 E0 yesterday and have been working on overclocking it.

First I decided to find out how far my FSB would go with this P35 board.

I jumped straight to 470MHz with 6x multiplier (1:1 ratio on memory) because I'd need this to get to 4.0GHz.

I had to raise the VTT to 1.37v and the MCH to 1.44v in order to boot up successfully and get into Windows. However that would only be stable for a few minutes. I raised the MCH to 1.48 but still only stable for a few minutes.

At this point I was hesitant to increase the VTT or MCH any further. I've read I shouldn't go over 1.40 VTT and my board doesn't have a 1.40 option for VTT, after 1.37 is 1.43. But I'm guessing I'd need more VTT to get 470FSB stable.


With 470MHz FSB apparently out of reach, I decided to back down to 460MHz.

With VTT at 1.30v and MCH at 1.33v I was able to Prime95 for 20 minutes, so decided it looked good enough and increased my CPU multiplier to 8.5.

I had to increase the VCC to 1.39v and was able to Prime95 this for 8 hours. I'll need to do more, but so far I'm feeling good.

Temps averaged around 50 to 55C across the 4 cores under load at 3.91GHz with 1.39 volts.

Is 1.39 volts going to be safe for everyday use? I had thought I'd be good with anything under 1.4v for everyday use, but a few moments ago I saw someone say 1.3625v.

 

[Snakebitten]

My old 65nm quad was able to reach 466-475 fsb on my IP35 pro but with my new Q9550 I can only hit around 440-450. I have my MCH at 1.48V but my VTT is only at like 1.13

I'm not sure if you need so much VTT pumped into your chip, I'd recommend putting more volts into the MCH and adding a fan onto your northbridge.

I've kept my MCH @ 1.48V since I purchased the board last October and I've heard stories of people keeping their northbridge at 1.55-1.6V for every day use.

As for Vcore, 1.4V or below for everyday use is fine. I have my Q9550 at around 1.33V. Intel specifies 1.3625V for max allowable voltage on the Q9950 but this is typically conservative and partly for warranty purposes.

 

[ballistic]

Just curious what temperature your PWM sensor is recording when you are running a FSB like that?
I agree with Snakebitten about putting a fan on your NB and upping the MCH volts, I would also think about putting a fan on the "PWM" heatsink.

I was seeing temps around 80-90c at 8x450 until I tossed a fan onto it and they dropped to around 65-70c, I don't know if it was limiting my overclock (I didn't really try to go higher) but seeing the lower temps just helped my piece of mind.

 

[Snakebitten]

When I had my 65nm quad, my PWM's were typically at 70-75C load. This is with a small fan over the northbridge, fan over pwm's and using the heatsink bolt mod for this motherboard.

The same setup with my Q9550 is showing a temperature around 50C load on PWM's. Everything is cooler all around with this new quad but I'm unable to overclock the FSB as high, I'd assume its because more data is being transfered since the 45nm quads are 5-10% faster clock for clock when compared to 65nm quads.