Core 2 Duo E7600 Question

[PiraticaL]

Good morning everyone,

So I need some opinions/advice on a recent overclock that I did. This was my first build and overclock using a mix of old and new and I thought I had everything just the way I wanted it. Initially I had a stable clock of 3.80Ghz with a vcore of 1.296V. Prime95'ed it for an hour no issues with my highest temps reaching around 48C. The only thing was my memory speeds were only 794Mhz instead of the full 800MHz.

So I decided to slowly raise the FSB to stay close to 3.8GHz but reach the full 800Mhz that my RAM can handle. Once I reached the 800MHz with a 5:6 ratio the cpu ended up being around 3.83Ghz. I had to increase the voltage a little to 1.32V because it would hang up and my screen would "freeze" with the voltage at 1.296V during stress testing

Anyhow it seemed I had a stable clock of 3.83GHz with a vcore of 1.32V. Prime95 ran for about an hour with no errors or warnings. Mind you when I reset the computer in order for these settings to take effect it booted up fine. Highest temps were around 49-50C. However, when I tried to turn on my computer this morning it wouldn't boot. I reset the CMOS and set everything back it booted fine on the reset but not when I had power completely off. But now once I backed it down to the first setting and voltage at 1.296V is boots up no problem.

Now I know there's not a drastic difference between 3.80Ghz and 3.83Ghz but I was hoping to get the full 800Mhz out of my RAM. I forgot to mention that the reason I am increasing the FSB to adjust the RAM speed is that my mobo auto links it and I can't change just the memory divider in BIOS. Any ideas on what I could do or just leave it at the setting with the lower voltage? I don't want to screw something up by constantly fiddling with it or throw more voltage than I really need at the cpu. Below are my components that I'm using.

Mobo- XFX 750i
Cpu- Core 2 Duo E7600 3.06GHz (stock)
RAM- 2x2GB Gskill 800MHz
Cooler- Zalman 9700
GPU- GTX460 superclocked

 

[jimmysmitty]

Did you make sure to set your memory voltage? That might be causing issues if its running at lower than the specified voltage.

I am going to assume you have DDR2, in that case most DDR2 800MHz runs at 1.8v but some will run at around 2.1v. Check your memory sticks as they should have the full specs on it.

 

[PiraticaL]

Yes it is DDR2. Forgot to mention that. If I remember right from my BIOS settings my default memory voltage is set to 1.9V. I didn't think that I needed to add to that voltage since I really wasn't exceeding the speed of the RAM. Do you think it'd be worth a shot to try to bump the RAM voltage?

 

[PiraticaL]

So as I got to looking into my memory settings some more it looks like my mobo auto set my RAM timings to 2-5-5-15 with a bank cycle time of 24. I manually reset them to the rated 5-5-5-15 with a bank cycle time of 20. I might try to adjust the FSB a little this afternoon once I'm off work to see if the timings were the cause.

 

[jsc]

Don't worry about the RAM speed. With the nForce 600/600 chipsets, try to run "Linked". That will put you at the FSB:RAM ratio of 1:1 (best stability). Your RAM clock will be two times the FSB freq.

You will not notice any system performance increase by running the RAM a little faster than the FSB.

I have a better idea. A lot of E7200 series CPU's will run past 4 GHz.

Go back to stock settings. Run the CPU multiplier at max (11.5). Set mem to Linked.

Start pushing the FSB upward. At 333 MHz, you will be close to 4 GHz. Your memory will be running at 667 MHz. That means that for DDR2-800 memory, it will be very stable. And the faster CPU speed will give much more performance than trying to maximize memory speed.

 

[PiraticaL]

My multiplier is 11.5 already and my motherboard won't allow for the mem to be anything but linked. Thats the issue I am running into. My FSB is 331Mhz with a voltage of 1.296V. CPU is 3.80GHz with mem linked they are at 397MHz (DDR2 so 794Mhz).

All I wanted to do was bump the FSB to 333Mhz in order to get the memory to 800Mhz which would put my CPU speed at 3.83Ghz. I know its not a lot and probably wouldn't make a noticeable difference but it was just the aspect of fine tuning it that I was going for.

I tried it again after I set the memory timing. Same thing, its all fine and dandy at 3.80GHz, FSB at 331 with voltage at 1.296 it'll come up from a cold start and all that. It will restart and take the settings of the 333Mhz FSB but will freeze in Prime 95 with the voltage at 1.296 and 1.3 At 1.32v it will run Prime 95 no errors but it won't boot from a cold start with it left like this.

The only thing that really throws me off is that it will restart just fine but as soon as I shut it down completely its not happy. Kinda strange. You wouldn't think that a 2 MHz bump in the FSB would require upping the voltage 2 notches or that it would be so angries when starting up.