Strange Changes in my Opty 165's Frequency

[bebop06]

I'm running an Opty 165 at 2.52 GHz (FSB 280, 9x multiplier) with 1.375 Vcore on a DFI Ultra-D (temps are always low: usually 30 idle, 34 under load). After I boot into Windows, MBM 5 says the opty is running at 2.52 GHz (as it should be). But after a few hours of running programs, MBM 5's reading has changed: so far I've noticed it dropping to 2.4 GHz and rising to 2.604 GHz. Is the DFI motherboard somehow automatically shifting the overclock? I doubt this has anything to do with stability, but when I tested the system under dual primes it froze after 22 hours (I think under small FFTs? It handled large FFTs for 24 hours). I know that means the system is pretty stable, but just thought I'd mention that.

Is this anything I should be worried about? Thanks in advance for the help.

 

[Shimmishim]

i dunno why it'd fluctuate only 100 mhz or so. do you have cool n quiet enabled? i doubt it but it might be the culprit.

 

[evilsaint]

Originally posted by: Shimmishim
i dunno why it'd fluctuate only 100 mhz or so. do you have cool n quiet enabled? i doubt it but it might be the culprit.

It's worth checking, but I think C&Q only lowers fan speeds/VCore, and that's only really when the system is idle, not when it's being used regularly.

OP, what type of PSU do you have? How old is it? Include your total system config too, if you don't mind. I would imagine that voltage fluctuations large enough to raise or lower the HTT or screw with the multiplier would've fried some of your hardware by now, but stranger things have happened

Have you checked the voltages when this speed-shift has been occurring? How stable does your PSU seem, for the most part?

Also, keep in mind, MBM is very useful, and for the most part accurate, but any piece of software is capable of giving an incorrect reading.

 

[DetroitSportsFan]

Originally posted by: evilsaint

OP, what type of PSU do you have? How old is it? Include your total system config too, if you don't mind. I would imagine that voltage fluctuations large enough to raise or lower the HTT or screw with the multiplier would've fried some of your hardware by now, but stranger things have happened

Have you checked the voltages when this speed-shift has been occurring? How stable does your PSU seem, for the most part?

Also, keep in mind, MBM is very useful, and for the most part accurate, but any piece of software is capable of giving an incorrect reading.

My first inclination is to also suspect the PSU. I think evilsaint's suggestion that you post your total specs as mentioned above is the first step.

Voltage fluctuations can also be caused by bad capacitors. In your case, I'd look at the capacitors that surround your CPU. Look for signs of excess heat such as discoloration, bulging top or bottom of the capacitor, signs of leakage on your motherboard, etc. If its a cap, and if you're good with a soldering iron, a capacitor can be replaced for only a couple of dollars.

 

[bebop06]

Here's my configuartion:

Opteron 165 at 2.52 GHz (280, 9x)
DFI LanParty Ultra-D
G.SKILL 2x1 GB PC4000 at 252 MHz (a 9:10 divider)
Sapphire Radeon 1900XT
WD Caviar SE WD2500JS (250GB SATA 3.0Gb/s)
PSU: PC Power & Cooling 510 SLI

I doubt it's the PSU, since I just got it last year and PC Power & Cooling are supposed to be super reliable. I'm not sure if this matters, but ever since I built it, my system has occassionally froze at the BIOS screen when I reboot after running it for a while, though it's fine after I power it off then on. I think this freezing have to do with my RAM, since it went away when I substituted my old 2x512 MB Corsair RAM.

And apparently it's not just a range of 100 MHz. I just quit out of Rome Total War, and MBM 5 displayed 2.24 GHz, then jumped up to 2.271, where it's stayed. Just after exiting the game, MBM 5 put my Vcore at 1.37--and though I have it set at 1.375 at BIOS, MBM always read it at 1.34. The temperature is a bit lower than normal--it's jumping between 29 and 30 (usually it's always 30 at idle, never drops below).

If it's a problem with a capacitor on the motherboard, is there any other way I could tell? I'm not terribly experienced with electrical stuff, so I'm not sure if I could tell by looking.

Thanks.

 

[bebop06]

Update: I just ran CPU-Z, and it shows the Core Speed jumping around 2515-2521 MHz (though most of the time it's 2520.x and is jumping around in the tenths place) with the Vcore at 1.344 but occasionally jumping to 1.36. Is this normal? Is that Vcore jump normal? And why, if I have the Vcore set at 1.375 in the BIOS, would it be at 1.344? I've heard that CPU-Z reads the voltage a bit lower than it is, but I didn't think it was more than .2 or .25 v off.

Is there any sort of program I can run to see if the voltage is unstable? What sorts of problems might this cause?

 

[Maximilian]

My Epox 9NPA+SLI fluctuates the voltage, what i have set in the BIOS is the max it will give the chip, but it basically feeds the chip whatever it needs, i believe your DFI is the same.

As for the clock speed fluctuation, only thing i can think of that would do that is the dynamic overclock feature present in some motherboard's, but that wouldnt explain why it would drop to 2.4ghz.

Check the BIOS for a setting that could be causing this. I know my Epox board can dynamically overclock the cpu, i have that disabled though as C&Q works fine for me.

 

[DetroitSportsFan]

If it's a problem with a capacitor on the motherboard, is there any other way I could tell? I'm not terribly experienced with electrical stuff, so I'm not sure if I could tell by looking.

Here's a LINK. You can read up on it there. There is also some good pictures to help identify bad caps.

P.S. If it turns out to be bad caps, check to see if your Motherboard is still under warranty. Its not that old so it probably still is.