Best overclock for 2.8 P4C?

[asadovsky]

I'm running a P4C 2.8 ghz with a P4P800-Deluxe mobo. I have Corsair TwinX 3200LL (1 GB total) ram right now. I plan to use the stock heatsink/fan (has a thermal pad). What do you guys suggest for me in terms of overclocking? I don't want to do anything that would lower my system's lifespan, so I was thinking that going around 230 FSB with a 5:4 ratio would be good. I haven't checked that for stability yet, but I know that when I tried 240 FSB at 5:4, Prime95 crashed gave an error almost immediately. Do you think I need different RAM if I want to OC? And if so, what kind?

 

[bjc112]

Well PC3200 is only rated up till 200mhz, after that you need to relax timings...

My hyper X 3200 does 220 FSB stable.. 2/3/3/6

I would first see if you can get a stable overclock at the 1:1 ratio... Try about 210 FSB...

Then when you hit that max, move on to the 5:4 ratio...



Your prolly gonna plop in somewhere around 3.2 ghz or so..

 

[asadovsky]

Right, but I don't understand why my system wouldn't boot at 250 FSB when I am using the 5:4 ratio. Wouldnt this make the RAM run at 200 fsb, which it is rated for? I tried that with 2/3/3/7 timings (2 = CAS latency) but the system wouldn't boot.

bjc112 - when you say you are at 220 FSB stable, do you mean with a 1:1 ratio or a 5:4 ratio?

 

[bjc112]

On my 8rda+ that's a 1:1 ratio..

Up your Vdimm voltage (2.7)

And your Vcore a notch...

Report bacK!

 

[asadovsky]

I'm at work, so I can't try that at the moment. I'll set the DIMM voltage to 2.75; what should I set the Vcore to? (I assume Vcore = CPU voltage). Keep in mind that I want a stable system that doesn't get too hot, and that will last for a while.

 

[bjc112]

The BIOS should have a 5%, 10% increase and what not...

I think defualt for a p4 is what? 1.4?

Don't go above 1.6 unless you want that Northwood to die out of the blue...

 

[asadovsky]

Well, in the BIOS, the LOWEST cpu voltage is around 1.525 I think. It's definitely not lower than 1.5. Are you using the AI overclock feature? I was planning on OCing manually, as this would let me tweak the settings so that everything works. However, as I said before, the system for some reason wasn't stable at 240 FSB with a 5:4 ratio, and I still don't know why.

 

[jpetermann]

Corsair will take 2.8vdimm all day every day no problems. Your Cpu should not be set at anything above 1.6 inthe bios, as Asus tends to overvolt a little bit. You may need to turn the vagp up a little also... try 1.6 and see if it helps. My 2.8c does 250 fsb stable, and so far, I have been able to do 260fsb and get into windows. Not stable for 3d, but i can run some benches at 260.

 

[asadovsky]

On the Asus P4P800-D, though, the voltages for the DIMMs must be set at 2.55, 2.65, 2.75, or 2.85... is 2.85 safe? Also, we are using different RAM, which may be part of the issue. I have been leaving the AGP voltage on auto... I didn't think it affects the overclocking.

 

[OddTSi]

Originally posted by: asadovsky
Right, but I don't understand why my system wouldn't boot at 250 FSB when I am using the 5:4 ratio.

Well, 250MHz FSB with a 2.8GHz chip would put it at 3.5GHz. Maybe your chip just can't OC that much, hence the reason why it's not booting.

 

[asadovsky]

Some people have gotten a 2.6C to OC that much... I think a 2.8C should be able to, shouldn't it? Then again, I am using stock cooling. Also... I have another question to tack on: will the RAM be slower if I use a 5:4 ratio and find that the system is stable at, say, 230 FSB? This would put the RAM at 184 FSB, which would be less than the 200 FSB it can reach if I use a 1:1 ratio.

 

[jpetermann]

2.85 is safe for the Corsair. The VAGP is important on high overclocks. It also feeds the Northbridge, which seems to need the extra juice...
THis chip will do 250 5:4 as well with thi OCZ Gold, and with OCZ 3500EL that I have had. Also, it might just be your chip. I get 250fsb at 1.55 vcore. It is always the luck of the draw!

 

[Chumpman]

Originally posted by: asadovsky
Some people have gotten a 2.6C to OC that much... I think a 2.8C should be able to, shouldn't it? Then again, I am using stock cooling. Also... I have another question to tack on: will the RAM be slower if I use a 5:4 ratio and find that the system is stable at, say, 230 FSB? This would put the RAM at 184 FSB, which would be less than the 200 FSB it can reach if I use a 1:1 ratio.

a 2.6 at 250 FSB is a lower clock than a 2.8 at 250 FSB, and I doubt you can make it to 3.5 on stock cooling

 

[asadovsky]

Hmm... I don't really need to overclock like crazy, I just want my system to run up to its potential. Supposing I want to run at 240 FSB, what would be good voltage levels and RAM timings for everything? I had tried 240 FSB with auto CPU voltage, 2.75v RAM, auto on AGP, and 2/2/3/6 timings, but Prime95 gave an error immediately. In the BIOS, it showed the CPU was running at about 43-44 C. What do you guys recommend? Should I shoot for less than 240 FSB? Is my RAM holding me back at all?

 

[topdog]

mine 2.8c clocked @ 3.5 250 fsb but not stable, fail prime on first run, lockup on 3dmark... 2 x 512 hyperx 3500 5:4 ratio 2.7 volts vantac fan w/sk900 hs

 

[asadovsky]

My goal isn't to OC as much as possible with boot; I simply want a decent OC, with stability as first priority. If I can't reach 250 FSB, so be it. Even if I can't hit 240, thats just fine. But I need to know what settings I should work with, what voltages are safe, etc., so that I can know where to draw the line.

And by stable, I mean that it should be able to run Prime95 for a good amount of time with no errors.

 

[asadovsky]

I just realized something... I am using a 9700 Pro, and I remember in the Asus manual it says that these may be unstable for OCing with the P4P800-Deluxe unless they are revision 30+. Mine's revision 11. Up till now I thought that was referring to OCing the video card, but maybe they meant OCing in general? I think I'll call ATI and see if they can send me a newer revision 9700 Pro.

 

[bjc112]

Why don't you just go for a 220 FSB and go up gradually when you get home...

 

[asadovsky]

That's what I'm planning to do. You are talking about at 5:4 right?