Reasons for OC's becoming unstable

[ETNiES]

I'm just wondering what some of the reasons are for a stable overclock of 6-ish months to become unstable as this has happened to me with my i7 920 4.0 OC.

The only reasons I can think of which i've tried to compensate for are..

Temps.. so I reapplied thermal paste, cleaned out the dust etc.

Voltages.. I know power supplies slowly become less efficient over time I was thinking this could have caused the unstable OC so i upped the vcore a little.

I can't really think of anything else that could cause it, I'm normally able to solve stuff like this on my own so before I reset and start again I wanted to see if there was something I was missing..

The only time I seem to freeze is when playing Enemy Territory (which only uses 1 core).. Never freeze in Windows, and the OC passes the Intel burn test on maximum with no problems.

 

[Danm54]

Heat as its summer.

What temp monitoring programs are you using?

 

[Andrew Moore]

Nasty horrid build up of dust is usually the main issue.

Remove this from the heatsink, the sinks on the mobo, the fins on the ram should it have any and also where you can from dust filters etc in the case.

Its amazing what a little dust can actually do.


Andy

 

[ETNiES]

I'm using Realtemp, all my temps seem fine, atm in a warm room with all fans on a Antec 902 case on low temps are, 40,43,42,41.. normally they are in high 30's but it is warm.. Using a Cogage True Spirit on a Push/Pull config with 2 Apaches.

I originally thought it was dust too but I completely cleaned the whole case dust filters etc, removed heatsink reapplied thermal paste etc.

 

[el Kuarlos]

Can be so many things...

Overclocking you are pushing a lot of tolerances, only thing you can really do is take the thing you think you are pushing most, back it down and see what happens.

Can simply be the way a certain program works...

My ram, badly mismatched 2000htz gskill in an amd 965 build will hold flawlessly at 7-7-7-18/1600 in everything but stalker, where it wont do above 8-8-8-24/1333, but it was hard to learn the ram was doing that...

MOAR VOLTINGS!

No seriously the reason parts have so much oc room is that there are so many different kinds of loads...you are just stressing the limiting factor in your OC doing what you are doing...have a play, let us know what works.

 

[rjk]

dust is a killer. it is one of the main reasons we get calls at OcUK about failed clocks over time. 99.9% of the time when people clean their heatsinks off their overclock becomes fine again

 

[robin66]

A small paint brush and a can of air work wonders.

I'm also glad I don't smoke or have cats in my house.

But I agree with el Kuarlos, it's just a matter of elimination now to find out what might be the weakness in your system.

 

[xiphrex]

If its unstable only when playing a 3D game then you should look at your graphics card, there may be dust there.

 

[sja360]

cant it be due to your psu? as with time the psu fails to produce the same voltages after years of load? just guessing ofcourse
you can check this by using a multimeter and see what the 12v line produces.

 

[mmj_uk]

As Danm54 said, overclocks tested in the Winter aren't guaranteed to be stable in the Summer.

 

[thingemajib]

imo cat hair does more damage than dust, bacause its much more likely to get stuck and build up. ive only had my cpu cooler running 3 months since i last had it in bits, and there was already a noticable covering a dust/hair behind the fan

 

[HW91]

I think it's the memory not the cpu, maybe you should try turning the speed down

 

[Danm54]

Next time it fails then see if your ram is hot to touch, if you're pushing that then the recent temp increase could have pushed it over the edge.

I had that problem and just put another fan over the ram, worked fine for me.

 

[smohieddin]

I've found re-applying thermal grease every couple of months usually solves my instability issues with what is normally an extremely stable overclock.

But as mentioned, it's probably caused by the summer temps.

 

[C64]

Could be that what you thought was a stable overclock wasn't.

 

[ETNiES]

Could be that what you thought was a stable overclock wasn't.

It's been stable since October so I doubt it's that.

Dust is definitely not a problem as the inside of the pc is spotless, including the heatsink and everywhere else, was going to reapply thermal paste on my 5850 but haven't got a screwdriver to fit the backplate screws to do it tonight so maybe try that tomorrow.

I have a set of Crosair Dominator fans might try them next see if it's maybe the ram overheating.

 

[JonJ678]

I'd go with C64 on this one. There's some very weird ideas of stability floating around. Processors make mistakes occasionally, even at stock speeds. It's heroically optimistic to believe they'll run a twice rated frequencies and make no mistakes at all.

Other option is windows is falling apart. It is known for doing this. Or ram spontaneously failing. Ram is also known to do this without any particular warning. PSU voltages will droop with time, but the atx spec is so relaxed that I don't think this is a common problem.

Or that all the overvolting you thought was safe is degrading parts of the chip faster than you hoped it would. If adding voltage fixes it, but you're sure it was "stable" before, that's a bad sign.

 

[ETNiES]

hmm.. I just turned off my overclock profile in bios, and the crashes stopped in game but I get huge fps drops and my sound cuts out for at least a minute and then comes back on again..

Might I of damaged something whilst overclocking? Gonna run memtest to check my ram.

I think i'm gonna format because I've been having problems with windows lately (mainly activation ones )

 

[ETNiES]

Annoying, after resetting my bios i.e losing my overclock settings, I formatted and it fixed the problem..

Weird thing is, the windows 7 x64 installation was only about 2 months old, I had ran a virus,spyware and registry scan all were clean, the only thing that was wrong was a slight activation problem (one I never seen before) Bill must busy

Thanks for the suggestions.