JAFFA

Hey hey,

I've been a busy boy today, I dismantled my rig and had a little tinker with it... First I did a pencil mod for VDIMM, previously it was undervolting to 2.35v when set to 2.4v in bios, I pencilled in the appropriate bit and raised VDIMM to give me 2.45v when set 2.4v in bios, not a lot I know but at least it isn't undervolting anymore. Next I did a VMCH pencil mod, previously it was also undervolting, 1.8v in bios would give me 1.75v actual, I pencilled it in an raised it 0.2v so when set at 1.7v I get 1.85v actual and if I raised it to 1,8v bios (which I havent so far) that would give me 1.95v actual.

Anyways, once the mods were done I grabbed an old IDE drive and installed a heavily butchered copy of XP Pro and set about trying out these mods to see if I could break my previous max FSB of 441 MHz (3950 MHz CPU speed)

I took it real easy to start and double checked that the clocks I was getting before the mod were ok and stable. They were so I pushed on... and here are the results:-

VCore 1.54v
VMCH 1.85v
VFSB 1.4v
VDIMM 2.45v
ICH 1.2v
9 x 444 1:1 = 4002MHz


I got a rounding error at this point and upped the VCORE a tad.

I kept going...
VCore 1.58v
VMCH 1.85v
VFSB 1.4v
VDIMM 2.45v
ICH 1.2v
9 x 448 1:1 = 4031 MHz


The computer locked if I tried any higher and I pretty much assumed I'd hit the limit when I remembered eva's post about raising TRD to 7 and TRFC to 42 to help FSB... I was already at TRD 7 but it is one of the lower settings on this board so I upped it to TRD 8 and it pretty much unleashed the board to it's full potential, I guess some boards are more sensitive to TRD than others. I was concerned that it would give a big performance hit so dropped my TRAS to compensate, dunno if it made much of a difference mind you.
So I kept going...
VCore 1.58v
VMCH 1.85v
VFSB 1.4v
VDIMM 2.45v
ICH 1.2v
9 x 450 1:1 = 4050 MHz


And going:-
VCore 1.58v
VMCH 1.85v
VFSB 1.4v
VDIMM 2.45v
ICH 1.2v
9 x 453 1:1 = 4076 MHz


And going:-
VCore 1.58v
VMCH 1.85v
VFSB 1.4v
VDIMM 2.45v
ICH 1.2v
9 x 455 1:1 = 4102 MHz


By now I was sitting there thinking to myself 'it's bound to crash, there's no way this is possible... I just aint that lucky'

I pushed on, but 32M errored out after 6 or 7 iterations, but luckily I had done a quick glory run at these clocks:-
VCore 1.58v
VMCH 1.85v
VFSB 1.4v
VDIMM 2.45v
ICH 1.2v
9 x 459 1:1 = 4132 MHz




I didn't try higher than that, I'd acheived more in a day than I dared dream of and besides it will give me something to do another day and I'm pretty confident that there is more in there somewhere. 1.58v VCore is fairly low really and temps never raised above 61c which bodes well.

So that's 4.1GHz Single 32m stable and 4.13GHz 1m Stable all air cooled , I'm well happy with the result, but I won't let it rest there... I'll have a week of actually using the PC and doing computery things and perhaps next weekend I'll have a crack at 4.2GHz aircooled

Thanks to SLi, Alpha and Jammer for all the help and encouragement.

All the best

Maff

dinos22

me looks for CPU stepping in the thread and cannot find one

SLi_dog

Awesome job Maff

4.1Ghz air cooled, nice. I gotta try that one of these days. The air cooled World Record is around 4.5Ghz and that's probably a suicide shot so you're damn close. If you added some insane 120mm fans to the Tuniq Tower on one of those cold english nights I wouldn't be surprised if you could get there.

I might have some tests to report with a setup of that nature soon



With air results like this Maff, there's really no need to use the Prommie. You might get some higher FSB with the colder CPU but not too much more.
You could always try the Prommie on the NB 550FSB

alpha0ne

Brilliant times JAFFA

Are you booting @ 400 in all those pics and using CG/SetFSB or booting at the displayed speeds ??

I think CG

SLi_dog

It's a 975X board so shouldn't make a difference.

alpha0ne

Senility is well and truly setting in now

JAFFA

@dinos, sorry dude totally forgot about the stepping it was very late at the time. It is a L628A276 (Pick date 21/8/06)

@ SLi I gotta confess that I find air cooling and the Conroe more fun than when I had an Opty under Phase change. Having said that I got a quote of £250 from Gray Mole to get my Prommy re-fitted with a chilly head and a re-gas which is pretty reasonable. It'll probably be new-year before I get the prommie together.

@Alpha I boot in at 420 and take it from there, It seemed like it was taking ages to clockgen up to 440+ when booting in at 400. I never tried booting in at 4GHz

Oh, and here is a pic of the setup...

SLi_dog

Get a chipset mounting head and put the prommie on the northbridge


Damn, I love naked computers almost as much as naked women. With both, each different one has a new layout and interesting bits to play with .
Wicked power/reset switch mod mate! Gotta be carefull about static from the carpet though eh?


The Lian Li slide out motherboard bases are just great aren't they. Anyone know if you can buy these separately? I'm thinking of cutting one to fit sub zero insulation.