So i just upgraded with a p5n-d 750i mobo,q6600,4 gig plain corsair xms 2 gig modules w/heat speaders, zalmann cpu cooler (its a good one),but kept my sli'd 8800gt's ,i cant get a stable overclock above 2.6. I had an a8n32sli w/ 4800+.So is the ultra xfinity 500 watt causing all the trouble?
Also am using nzxt lexa w, 7 fans, lighting,2 sata raptors,2 dvd, maybe 500 watt is getting pushed even on 2 12v rails

It's possible the PSU isn't capable of supporting it all. But you should be able to get to 3ghz on less then 1.3v which about stock.

What do you have the cpu voltage at?

LoL. Id say your under powered.

Try with one 8800, if you get results then you shall know. Disable most of the fans and lighting during test also.

How much vcore did you feed it?

That is a little odd.

Even my B3 runs 2.7Ghz at 1.15v bios
I run a shint 650w coolermater PSU, 4 sticks, hdds, water, 8800gts 320

Id say try unplug one gfx card and only run one hdd. If u get better results its the psu. Assuming u actually KNOW how to OC

Ultra is one of the worst PSU's anyone could buy.

its the motherboard. friend of mine landed that board, found some setting's on asus' forum where a guy got it to 3 ghz using very specific settings. i havent had a go at it yet, but he ran into nothing but trouble too.

Yeah Lucius has a point. You should be able to overclock to 3.0ghz without adjusting the voltage. So I really can't see how the PSU can be realted. I can underpower my q6600 and still run stable at.3.0ghz.

I'd remove/disconnect everything that isn't essential and see what happens. Also check which stepping your CPU is. If it's G0 it shouldn't be a problem. B3's are much worse for overclocking.

i adjusted all voltages from 1.24 to 1.38 and tested,but cant believe i forgot to try just 1 gpu,if that doesnt work i guess my mobo sucks at oc'ing, thanx guys

CPU will still pull more wattage when it's overclocked, so I wouldn't rule out a bad PSU just yet. In fact, if you don't have a good PSU, you risk burning out your whole rig and costing you more than you would have buying a better PSU. So I'd upgrade it in either case

Doh i completely forgot about that. Sure the voltage is the same, but the current draw increases. So yeah PSU being too weak is becoming more then a hunch.

Since my PSU is 750watts it's no wonder i had no issues.

Yeah I totally forgot about that too.

http://www.tomshardware.com/forum/ [...] rd-problem

I second this. Ultra sucks. They have a wide array of problems to include giving out at only 50% of their rated max when current draw is high. Swap out that PSU wether it's part of the problem or not! Your wallet will eventually thank you for it, you can mark my words on that. Also the 750i is a known inferior overclocker even though it can be done.

http://www.hardwaresecrets.com/article/534 - "How Much Power Can a Generic 500 W Power Supply Really Deliver?"