# OC'd system stability problem



## Cdaman (May 28, 2006)

Hi all,

ive got a problem with my system stability.

Just decided to upgrade my dying 4 year old pc in order to play newer games better.

i purchased two sticks of 512mb corsair pc3200xl cas 2225 to increase my ram to 2Gb.

Ok heres my problem, now i have 4 sets of 512mb pc3200xl running my system it will quickly Fail Memtest when i OC the FSB to 240, but will pass if i only use 1gb (2 sticks @ 240) or use a FSB < 220(with 4 sticks).

i originally thought it may be faulty memory, but it looks like it could be power problem, as this memory should overclock further . Has anybody else had a similar problem and knows how to fix it?

im running
p4c800e duluxe
p4 3.2e s478
Corsair cmx3200xl cas 3-4-4-8 @2.75v (512x4)
Antec truepower trio 650w
His radeon x1950pro
2 seagate drives in raid 0


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## manic (Aug 2, 2005)

I would say you have a stick of ram, or two that isnt happy with
each other voltage wise, or may just not be compatible, or bad.
It happens. You would want to be running in dual mode, so compatiblity
is a true key. You would have a better chance at using 2 matched 
sticks to achieve this versus 4 sticks, Ive had fair luck using 4 matched
sticks. Bout 50/50 for me...


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## 2pistolpacker (Dec 3, 2007)

I've also had about a 50% success rate running 4 identical sticks of memory. I was able to calm down a couple of the systems by raising the northbridge voltage, but some boards just don't do a great job with northbridge cooling, so procede cautiously. When someone asks, I rarely recommend running four sticks because of this. Mike


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## Cdaman (May 28, 2006)

Cheers guys 


looks like ive got 3 options. Which do you think is best?

1). replace the two sticks with a matched pair (as one pair already is matched). will i still have stabilty problems?

2) sell it all up and buy a matched (just two sticks) pair of 2gb DDR 500/550. will i still have stabilty problems if i go higher than 240 FSB?

3) or increase northbridge voltage.

I could only find a setting in my bios called AGP VDDQ voltage which has the options 1.50, 1.60, 1.70, and 1.80v. which i think is tied to the northbridge.

well i opened up my case, aimed a desk fan at my board and raised the AGP vddq voltage to 1.70v. i managed to run memtest for 4 hours with no errors. woo hoo!

Do you think i should buy fan for the northbridge cooler or invest in a new heatsink altogether? and then try 1.80v or is this way too much!?


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## 2pistolpacker (Dec 3, 2007)

The AGP VDDQ is the video card slot voltage and I would not raise that if all possible. If it were my system and I was having instability, I would back off the OC and test my components to be known good at stock speed. Then slowly raise the OC and test along the way. The only voltages you should really need to raise are the Vcore(cpu) and the Vdimm(memory). You're best bet is to sell the 4 sticks and buy 2 1gb sticks and procede from there. The issue with all memory slots full could never come into play. While you are running the computer touch the northbridge heatsink, if it is getting real hot put a fan on it. I use old 486 cpu fans for this. You need to remember that every piece of computer equipment has it's own OC'ing stability limit, when you reach that limit, which it sounds like you have. Only voltage or different parts will raise that limit again. Do a google search for Corsair cmx3200xl and Vdimm voltage, there is a lot to be learned from other peoples trial and error. Mike

Old Review


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## linderman (May 20, 2005)

I agree with the fellas above / I have never hit a systems max overclock using 4 sticks of ram


alos if you are using a prescott CPU you had better watch your temps carefully those run hot already!


in your shoes I would look for a matched 2gb pair (2 x one gig each stick) like the crucial ballistix DDR500 you will need to bump up the vdimm to 2.75 and probably the cpu voltage a touch too

dont go crazy / if you burn up that board you wont like the replacement costs ! even used your board sells for more than it was new!

you will need a good aftermarket cpu cooler and maybe even a better northbridge cooler

what cpu cooler are you running now ????


240 on the cpu clock is a hot clock for sure! you will really need to watch temps / have A+ air flow inside the case >>>> like two *high* RPM 120mm case fans >>>>> like 3000 rpm's >>>>> those will make your case sound like an electrical transformer; but ???????????? if will keep your system cool !


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## Cdaman (May 28, 2006)

Think i might start looking for a nice new set of ddr500

Thanks for your help guys

Im using a coolermaster hyper 6, it does a good job keeps my cpu cool at about 32 degrees idle, and 55 degrees under load. Anything higher than 57degrees triggers a reboot though!!!!, i thought prescotts could get hotter than that. ive also got two 80mm intake fans and two 80mm fans on the rear. i was also thinking about lapping my cpu to lower temps further, but havent got round to doing it yet. 

I also set the ram to 320 (5/4) and the max FSB i could reach was 247 so i think maybe is the most im gonna get to, but with some nice new ddr500 i should at least be able to do it with 1:1 ratio :smile:


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## linderman (May 20, 2005)

check the temps in the bios too ???? it shouldnt restart until it hits around 70C 

you may well & should be able to handle MAX work load temps of 60C with a prescott (while gaming)


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## manic (Aug 2, 2005)

I ran a 2.8ghz prescott cpu with a p4c800-deluxe, basically the same
board you have. Used a zalman for the hsf, did a good job. At idle
my temps would be around 108 degrees fahrenheit, but gaming
it would stay at 165 degrees fahrenheit, for a while I was real paranoid
about that temp, but as mentioned those cpus got hot. I was over
clocked to a hair over 3.00ghz, ran fine for a few years of heavy
use, loved the board, I ended up selling that system, and its still
running today afaik...those early prescotts did get toasty....


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## Cdaman (May 28, 2006)

Ok think i may have found the problem

Ive read around and is seems that the asus probe temps may differ from the bios temps. i looked at my bios temperature section and found it was set to do a thermal active temp of 60 degrees, which may be why it cuts out at a low temp. ive now set it to 70, but i havnt tested it out yet


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