Why is my FX-55 running so hot on load?

[WAZ]

My PC is an FX-60 with a Zalman CNPS9500 and runs great -- 30C idle, 44C load.

I just built a backup system using an old FX-55. First I used a well-reviewed Arctic Cooling budget cooler, but my temps were about 47C idle and 65C load. Figuring it was the budget cooler, I bought another Zalman CNPS9500, seeing as it works phenomenally on my FX-60. But no luck. 45C idle, 67C load (a little worse). I chalked it up to a poor installation on my part -- had some trouble with the screws and moved the heatsink around quite a bit -- so I tried one more time. Good install this time, using the Zalman... AND? 43C idle, 64C load.

I absolutely cannot get my temps to go down, with the load numbers being particularly worrisome. 3 HS/F installs, including the use of a very high quality Zalman, but load temps easily clearing 60 degrees. Why is my FX-60 doing great while I can't get this FX-55 to even operate normally? What else could it be?

 

[God Mode]

Maybe a subpar heatspreader bond with the core. Are the edges of the heatspreader higher than the middle?

 

[BonzaiDuck]

This is a naive speculation.

But I wonder if these problems might somehow be related to something that is failing in voltage regulation?

We've commonly looked at simple-to-fix flaws at the thermal interface, and I'm wondering if it might occasionally be a symptom of something else.

 

[WAZ]

Originally posted by: God Mode
Maybe a subpar heatspreader bond with the core. Are the edges of the heatspreader higher than the middle?

I'll have to check when I get home. Any reason this would be the case on BOTH a budget cooler and the high-quality Zalman?

Originally posted by: BonzaiDuck
But I wonder if these problems might somehow be related to something that is failing in voltage regulation?

I checked the voltage in the BIOS and it was 1.5V, as specified for the FX-55. It's not overclocked (running 2.61 GHz right now), but would the various clock settings have anything to do with it?

Or, is it possible the temps aren't being reported properly? Both SpeedFan and another program (CPU Core something?) report the same temps.... any issue with the Gigabyte GA-K8NS Ultra-939? The latest BIOS is from 2005...

 

[Noubourne]

Could quite easily be a difference in sensor. Not all sensors are equal. This is a large variation, but it's the most likely factor, next to a bad mount. Since you've tried more than one HSF (which means you've re-mounted) and it's not changing much, that rules out bad mount.

So then it could be the contact of the integrated heatspreader with the core. That's the factory installed cap on the chip. Of course, that assumes that the temp is accurate, which I would suspect before the IHS. The only way to test if the IHS was mounted poorly is to remove it and cool directly on the core. I do not believe it is possible to re-mount an IHS - you can take it off though.

If you don't plan to OC and it is not throttling or shutting down, then you should not be concerned that the temps are reporting high. Just put a decent cooler on it and trust that it is doing its job. If you do plan to OC, then you should consider taking off the IHS. It's not like you're going to RMA a chip you've OC'd anyway.

 

[WAZ]

Yeah, I was hoping it was just being misreported... In case I just "go with it", will the FX-55 shut itself down if it overheats, before being damaged?