Q9550 - DDR2-800 limiting my OC?

[sirsloop]

This Q9550 has a locked 8.5 multiplier, so in order to OC I have to jack up the FSB. Well, even at 1:1, you can only to go like 3.4ghz give or take before you max out your ddr2 800 ram. When I get over 400fsb, the system typically does not post. Am I correct in assuming that with adequate cooling, and DDR2-1066 ram, I could take this processor upwards of 3.8Ghz? I just installed the CPU cooler today and put a conservative OC on there with high CPU voltages, and its still only riding in the mid 50s folding. Figure add another .3-.5Ghz and take out .1-.2v and I should still be able to keep it under 65C

What ram should I get for this P5Q-Deluxe?

 

[MattNo5ss]

I would get 2x2GB G.Skill DDR2-1066 for the RAM. Also, I noticed you're using all 4 DIMM slots and that puts more stress on the NB, so you might need more NB voltage while OCing.

 

[redduc900]

Corsair XMS2 DDR2-800MHz RAM should be able to easily reach speeds in excess of 800MHz. Post a link to your RAM, showing SPD timings and default voltage. Also download MemSet, and post a pic. w/ it open showing all of the current DRAM sub-timings...

http://www.tweakers.fr/memset.html

 

[sirsloop]

http://www.newegg.com/Product/Product.aspx?Item=N82E16820145194

ill get the rest in a little while...

thanks for the info

 

[redduc900]

I'll still need you to post a pic. of MemSet, but w/ default timings of 4-4-4-12 at 800MHz, loosening the timings to 5-5-5-15-2T at 2.1V should net you ≥ 900MHz. So w/ a FSB of 450MHz at 1:1 (333/667 NB strap) and a 900MHz DRAM frequency, that would give you an effective clock of 3.82GHz.

 

[sirsloop]

I guess the auto voltage for these chips is 1.8v?

 

[redduc900]

Loosen tRAS to either 15 or 18, tRFC to 51 - 54, Write to Precharge Delay to 14 - 16, tWTR to 12 - 13, and adjust DRAM voltage to 2.1V. If you can adjust Performance Level (tRD) in the BIOS, try lowering it from 11 to about 8.

 

[sirsloop]

I'll give it a go and let you guys know how it works out. Thanks for the tips!

 

[sirsloop]

well its up to 3.655ghz, but it needed 1.392V (in win) to remain stable at it. I was unable to get 3.71-3.8ghz stable in prime95 running the max torture test. The machine would get into windows and run the small FFT or in-place large FFT no problem, but would instantly lock up once I started the Blend uber torture test. I guess its time to call it quits for the night. I have the nb running at 1.5, vcore reading 1.392V in windows, 430fsb. Temps are a little high... high 62-67's and core 0 seems to like 71-72C. I'm pretty sure the rest of the settings are set to auto. Any other things I could try to raise the fsb more without raising the vcore any more?

 

[johan851]

Does dropping vcore at this point make the system unstable?

I think you have too many variables here. I would lower the overclock on the CPU (put it back to stock or close to stock) and use higher memory dividers to find the maximum speed of the RAM first.

 

[redduc900]

If Windows is locking up while running Prime, then chances are it needs more Vcore. Does Memtest pass w/ the RAM at 860MHz?

 

[sirsloop]

Ran memtest as is and it locks up at 5% of the first test. I returned everything to auto, 2.83ghz, 799 on the memory.... memtest locks up at 5% of the first test.

So next thing Im doing is testing each stick individually, see if there is a bad one. Then i'll test them in pairs, then see if I can get all 4 going.. maybe thats the problem. I guess I could always just run 4GB. I was running a 4GB ramdrive before, but honestly it was a bit unnecessary.

 

[sirsloop]

very strange... so all of the ram made it through ok on single channel. When I paired them up the machine reboots at like 10% of the first memtest. I tried switching pairs, switching motherboard slots... no dice. wtf?

 

[RollingThunder]

Loosen tRAS to either 15 or 18, tRFC to 51 - 54, Write to Precharge Delay to 14 - 16, tWTR to 12 - 13, and adjust DRAM voltage to 2.1V. If you can adjust Performance Level (tRD) in the BIOS, try lowering it from 11 to about 8.

Bob,

I'll give you guys a lot of credit when you can analyze the sub timings and adjust them for overclocking. I have enough trouble running at defaults!

 

[sirsloop]

so I dicked around with it this morning for like 3 hours trying to figure out whats up... ended up just bringing it back to 3.665ghz running at 1.376V. idk whats up with memtest v3.5... even at completely stock auto settings nothing seemed to be working other than single sticks??

 

[redduc900]

Instead of running Memtest, use Memtest86+ instead...

http://www.memtest.org/

 

[vivek]

I would try upping the nb voltage and overclocking the ram to 850mhz or even more if possible (that will give u atleast 425 x 8.5 = 3.612 ghz) ...what r u shooting for with ur q9550?

 

[sirsloop]

Well, from what I've seen 3.8 seems to be a magic number with these things on air. To be honest if 3.655 is the highest this particular chip will go, that's not that bad I dont think! What should I be shooting for on NB volts? I've currently got it set at 1.5

I think im gonna chill out and fold for a while and maybe have another go at it tonight...