**Official DFI LanParty UT P35-T2R Review/Overclock/Guide Thread**

[Raja@ASUS]

I know exactly how you feel, my G0 stepping quad posts and boots to windows vista at 3.8-3.9ghz, but I am struggling to get it stable anything over 400mhz FSB on this board (3.6ghz), upto 400mhz I have the following settings and will blend prime all day and all week with my crucial ballistix 667mhz at 1000mhz:

CPU = 1.45v, RAM = 2.23v, FSB VTT = 1.38v, NB = 1.45v, SB = 1.15v, GTL's all currently Disabled, Clock Gen = 3.45v, mem is running at 4-4-4-12 @ 1000mhz.

However even at 401 FSB everything becomes unstable, I just dont get it, i've tried bumping up voltages etc and it doesnt seem to make any difference, im not willing to run the NB at 1.6v 24/7 as it already gets hot enough (47oC with a fan on it whilst blending).

I was testing memory earlier in case that was the problem, and the memory was stable no matter what dividers I used all the way upto 1000mhz 4-4-4-12, some of this testing was done with the board and the CPU at stocks, others required the FSB moving up and the multiplier on the CPU dropping to keep the CPU at stocks, but once again, the minuite I pushed the FSB over 400 it was failing memtest again, I think the setting I had on the ram at the time was 333/800. at 400FSB it was at 960mhz so I pushed the FSB to 416 to put the ram at 999mhz (1000mhz) and like I said it was failing memtest.

Below is a kind of review I just typed up for myself to keep myself in check, so I knew what I had tried and what I had'nt, feel free to download it and have a look, then hopefully someone might be able to answer both of our issues.

The primary mistake you are making is leaving the GTL ref's on disabled, even with VTT point of 1.38 and suitably applied GTL's you would see more success. The GTL's need to operate within a margin of VTT, typically around 1-2% within 67% of VTT, anything below or above this margin will likely fail to hold steady (unless you have a real freak processor)


A side effect of Cas 4 is that VNB and Vdimm will need to be higher than Cas 5 clocks. Check Kris's article on CAS related overclocking margins over at the Tech Repository.

Cas 4 on DDR 667 ram, which is not binned as Micron D9GKX, will need quitwe a voltage bump in some cases to scale, bear this in mind...

The 266 strap and divider combo's will operate Performance level 6 on this board upto around 463 fsb (266/667 divider). The 333 strap will give a margin of around 10-15 fsb over the 266 strap for absolute stability (333 strap loses latency and fsb overhead is a little low to claw back the deficit), however I feel that the 266 strap is the sweet performance ratio for Quad core clocking on this board (if not benching for extreme cpu mhz).

1.5vnb will get you 400fsb ddr 1200 Cas 5 on this board. Cas 4 gives the NB a harder time, so one has no choice but to bump VNB to provide suffcient overhead for the lower latency. 450fsb will require 1.61-1.65 VNB @ Cas 5 , with suitably low VDimm on good ram. 400 Fsb should come with VTT of around 1.50v (using the appropriate GTL ranges) and upwards, or less if you are prepared to put in the time to study how much VTT/GTL your setup can get away with.

It's just a matter of you picking a range of performance and voltages within the boards abilities at a point you are comfortable with (there will have to be compromises in both directions.

regards
Raja