P4 3.4C @ 4.3GHz need help OCing plz!

[OC_newbie]

I can't get 4.3Ghz stable it keeps restarting my system after an hour or so.
Not sure but I think it's because I need to up the volts for my memory, but I'm at max already. :( The reason why I believe this is cuz before I couldn't OC higher then 4.1GHz with 2.75VDIMM then as soon as I set it to 2.85 volts I was able to hit 4.25GHz and 4.3Ghz with Vcore around 1.72 and up.
Any help would be great.

[AlterBridge86]

hey there - only thing i can think of is to do the vdimm mod on your mobo, or get a OCz DDR Booster if your not good at soldering. I had a DDR Booster and i just recently did a vdimm mod to my P4C800-E and it worked great, actually better than the booster. If you do a search for vdimm mod i'm sure it will come up, or try out www.ocforums.com - they're very helpful and have good mods...good luck!

[blinky]

http://malvescorner.com/p4c800.html

http://malvescorner.com/images/p4cvdimm.jpg
if u wanna do the mods

and try a 3:2 mem ratio and then ull tell if its really your ram holding you back
i think the P4C800s can do 270fsb so thats not a problem

[OC_newbie]

Thanks AlterBridge86 I'll look into that.
Also you think it's because I'm using the Northwood core and not the Prescott core like you?
My BIOS version is 1016, I notice yours is the bate 1017 does that help?

[OC_newbie]

Ok Blinky thanks alot I'll try the 3:2 memory ratio tonight.

[OC_newbie]

Ok well I tried the 3:2 mem ratio at 253MHz and a black screen came up saying "Bad BISO Checksum. Starting BIOS Recovery."
So it must be my memory thats not letting me OC higher?
:confused:

[rhino56]

what fsb you at? and what psu you using?

[OC_newbie]

I have a Antec 480W ATX TRUEBLUE480 PSU, and im trying for 253MHz and higher but the computer restarts after about an hour. Guess I need to try that volt mod for my board. Or would a Prescott CPU be better at the same speed?

[rhino56]

I have a Antec 480W ATX TRUEBLUE480 PSU, and im trying for 253MHz and higher but the computer restarts after about an hour. Guess I need to try that volt mod for my board. Or would a Prescott CPU be better at the same speed?
are you sure its not heat related? what are you cooling the rest of the comp with? can you cool the ambient by a big margin and try it? like if your room is 75F can you get it to 65F? that would tell you if heat is the issue.

[OC_newbie]

The rest of the system is cooled by alot of fans, see signature for temperatures. Anyone have any other ideas why this is happening?

[Gogeta]

38c on the NB seems pretty hot, especially with a 159. I'm still using the stock Asus cooler on my P4C800, and NB temps never go above 33c according to MBM...and I only have 3 Panaflo L1A case fans. Did you use AS on the 159? Try re-seating the heatsink on the NB.

[rhino56]

i agree, 38 is too high, do you have a fan on it?

[OC_newbie]

Yes a 40x20mm fan @ 5200 RPM

[OC_newbie]

Ok I'll try reseating the heatsink on the NB tonight thx.

[OC_newbie]

well I took off the heat sink and fan from the NB, it looked fine so I put it back on.
I'm gonna try putting a fan over my RAM cuz I noticed it's very hot when my system is running for an hour or so, maybe that will help :confused:

[OC_newbie]

Hey good news I'm now at 4.4GHz!! :toast:
What I did was upgrade the fan on the NB from 5200RPM to 9200RPM, put a fan above my RAM, and Vcore is on 1.8V now.
I'm gonna do the Droop mod and Vdimm mod this weekend!