oc c2d e6600

[Outlaw]

Anyone familiar with the C2D e6600 and some oc? I think I am reaching the thermal limit of this CPU on the OC with my cooler. But after putting some AS5 on it, It may not be seating properly (have to pull board to be 100%). When I run prime95, I hit 63-64c. When I see it do that, i kill prime95. I can successfully run through 3DMark06 though but I don't know my temps while its running. For 3DMark, it reports the proc at 3.1 but the nvidia monitor and CPU-Z show it at 3.375 so I don't know if there is some throttling going on.

I have been reading quite a bit and still am not sure if I am reaching the Tjmax. Some sites say 70, some say 80 some or 85 or even 100.... not sure where to believe. Intel site just shows Tcase of 60.1


Temp below (42c) is about idle, it usually fluctuates between 39-42 until prime95 runs then it will spike to 60c+

http://3dmark.com/3dm06/15536242


note- while overclocking, my kids were helping me and they thought it was a "numbers game". lol

[slaveofconvention]

I'm no overclocking expert, but I think around the 3.5 mark is about as good as it'll get with a 6600 - as for the temps - well the CPU will throttle back before it gets too hot so you're PROBABLY ok to let it go instead of stopping it at 60...

[mDust]

The tjmax is going to be 80-85. I'd keep it below 70C for every day use though as heat will shorten its lifespan. It isn't going to throttle in the 60s. You aren't even to the recommended upper voltage limit yet so you have plenty of room to continue OCing...just get more cool air to the heatsink.

[Outlaw]

Thanks guys.

Slave- I stopped there because after seeing what looked like to be improper seating, I didn't want to push my luck. I think the temps would be better if it were seated better.

mDust- Thanks, I wasn't sure about that. Gives me a little more room to go.

I was also getting pc lock up while running the FC2 benchmark. Don't know if that is just cpu instability or ram yet. Since I came across the uncertainty with the cpu seating, I'm going to stop until I know for sure that its sitting correctly. Without the OC, my temps would never break 50 gaming. (i never ran prime95 though)

*update* dropped it down to 3038Mhz and it seems stable and not breaking the 62c mark. Mostly staying about 60-61 and spiking to 62 before dropping back down. I should take a picture too, but I think the H50 is partially to blame as there is big grooves on the copper sink. I can hear the noise my nail makes as it goes across the ridges. Looks like someone just took a belt sander with 300grit to it. lol

*update* got to go stable so far at 3.3Ghz. Idle is 40c, Load is about 62-63c

[mDust]

I should take a picture too, but I think the H50 is partially to blame as there is big grooves on the copper sink. I can hear the noise my nail makes as it goes across the ridges. Looks like someone just took a belt sander with 300grit to it. lol

Get yourself some 800, 1000, 1500, and 2000 grit paper and a known flat surface and then lap it. It will actually make a difference. Get it to a nice mirror finish. Those gaps probably trap air on top of the thermal paste which is a dead spot for heat transfer...If you get rid of them, you'll likely lower your temps by several degrees C.

Also, when you're OCing, make sure to isolate your CPU, mobo, and memory and max them each out separately so you know what limits you're hitting. If your CPU can OC further but your mobo can't, focus on the multiplier instead of the base clock...otherwise your base clock should be about as high as your mobo and memory will allow.

[Outlaw]

Thanks,

I did some reading on the lapping of the cpu/hs which like you said should definitely help. Just have to get the time to do it.

When you say to play with the multiplier, I can only go down (9 is the max), are you saying to lower that then raise the FSB and see if its stable? For the RAM, it is unlinked but has been adjusting itself. Right now, I think its at 1050Mhz and it is rated 1066Hhz. I haven't messed with the timings on it though, they are just set to optimal.

With the oc limit on the cpu, I think it still has some room, not sure how much, but it is fairly stable while using it day to day at 3.3Ghz plus but under prime, not so much. Since my last post, I did have to bump down to 3.263Ghz

Pic for some reference.

[mDust]

First, drop the cpu multiplier to minimum as well as the memory divider to slow them to a crawl. This isolates the motherboard. Find out how high you can get your bus speed. With the cpu and ram running below spec, the stability barrier you can't get past by upping voltages will be the limit of your mobo. You find this barrier by adjusting settings until you get prime95 stable for 10-20 minutes (or longer if you're patient or plan on stressing your system on a regular basis). Write down all the pertinent, successful settings.
Next, lower the bus speed to around 70 or so, and then set your multiplier to 9. Increase the bus speed until you max that out like the mobo. Officially, your chip is good to 1.5v, but I'm sure it'll be fine for everyday use higher than that if you feel it's necessary and can keep it cool. Google can help you find out what other people are doing with your chip and you can figure out from there how far you feel like pushing it. Again, when you find your limit, write down all the pertinent, successful settings.
Drop the multiplier to 6 and set the bus speed to the fastest stable setting you were able to run. Then adjust the memory divider so the ram will be running close to its rated speed. Unfortunately, the higher your bus speed, the larger the potential gap between actual memory speed and rated speed. Try the setting closest to rated speed even if its higher. Most memory doesn't like to run at a higher frequency than was intended but you might get lucky. If it boots, run prime95 and run the 'blend' test. OCing or simply optimizing ram can be quite tricky as you can either raise the frequency and loosen timings or lower the frequency and tighten timings. Overall memory bandwidth is > uber low timings...but lower timings are good too. Memory benchmarks are really the only way to tell what's best for your ram. If you don't really want to get into all that, just set the frequency as close to spec as possible (adjusting bus speed down *slightly* to get closer to ram frequency spec may be beneficial) and then lower timings and stress it again. Adjusting ram voltage is generally useless and can be dangerous...keep it where the manufacturer suggests. When you get it stable where you want, write down all pertinent, stable settings.
The last step is combining the highest bus speed and stabilizing voltages from your mobo settings with the multiplier and voltages from your ram settings and the divider and timings of your ram settings. Your system should then be screamin' along compared to stock settings. Run prime95 for 12+ hours to confirm 100% stability...or don't. Programs will crash and bsods will be somewhat common if the system isn't stable though. If you're hardcore, and the system is stable, you can lower voltages while maintaining stability to further optimize your system. I did it once. It was a pita...I decided I'd just deal with the extra 2C temps and $.03 per month on my electric bill. I guess it depends on how much you enjoy staring at your bios screen.

[Outlaw]

Thanks for all the info.

Time permitting, I will probably give it a shot tonight, at least a little bit and throw in an update when I'm done.


While it's unstable in prime but stable in games/aps as far as I can tell, does it even matter? Is prime and the like tools more for ultimate stress testing/benching?


*updated*
2hrs of lapping and it was IMO 100% better. You can see a reflection in it now. Also, idle is now down to upper 30's and right now, running prime is at 54 (3min in).

FSB maxes out at 1600Mhz. Pretty sure that is the board max running at 1.3v. Ram maxes out at 1066, didn't like 1100 and its already at 2.1v. CPU right now is at 2.8Ghz at 1.45v

Posted this update while Prime running 100% on both cores.

*picture update*
LAPPING. I do have progress pic's if anyone is interested. The heatsink was pretty concave.
Before:

After:

Load Picture for comparison. Normally with both cores loaded, I would see 63-64c and slowly climbing. This was only 6min load but still almost 10c less. I did peak a couple times at 60 which I'm OK with.

So far stable at 2.8Ghz CPU(2.4Ghz Stock), 1600Mhz FSB (1066Mhz Stock), 1066Mhz RAM (1066Mhz stock). Need to run overnight test, but no crashing in the 15min I let it run.

Also, I know it's not too much, but I'm proud of it, lol is that with the OC, it is comparable to my co-workers Alienware (stock of course). i7 and dual 5870's. He gets a 14800 in 3DMark, I get a 14222. I beat his frame rates in everything but the Canyon Run. And obviously his beats me in the CPU Score. He also beat me in HDR Score.

[mDust]

Stress testing in prime95 or similar programs guarantees that your system is stable under any conditions. Almost no other programs will stress your system as much so you can get away with a few prime95 errors as long as they are infrequent and you aren't doing anything mission-critical. If your computer isn't 'prime-stable' then it's likely it will crash on occasion...usually at the worst possible moment. ...like when you haven't saved your game in New Vegas in a couple hours because I'm an idiot...

That waterblock was dead and you resuscitated it nicely. Pro job!

[Outlaw]

Well, good news. Just ran prim95 for 3.5 hrs stable at 3.2Ghz CPU and 1.42Ghz FSB with ram stock at 1066. I also removed the push/pull of the 2 fans I had and put 1 high cfm fan on it. With that fan and the settings above, I topped at 58c in the 3.5hrs with 50% fan. I think I could get it to about 53ish but my wife asked if it was going to take off. lol

Also while prime was running, i was using the pc too. Hopefully this proves it stable. lol about Vegas, I have done that before already playing Zoo Tycoon with the kids (not prime stable).. lol

Thanks for the compliment on the cooler. Sadly it was purchased that way from the factory.. I'm glad it was fairly easy to do as I wasn't too sure on it from what I had read prior to doing it.

I am interested to see what I can get the temps to with a c2q I may be purchasing. It's a 95w stock vs my 65w.

Thanks for all the help,
Outlaw

ps. idling right now with 1fan on rad, im at 30c (it is somewhat chilly in the room though).

For my system board, 1600FSB being the max, I guess I can't complain as it shows being rated for only up to 1333. Not too shabby.