Unexplained rising CPU Temperatures

[moshee]

A couple days ago I noticed that my CPU (AMD Phenom X4 9850 BE) was beginning to idle at higher temps than normal. CPU activity was 0-1%. When I first put it together, it idled at ~30C and went up to ~45C under load. Now it's idling ~35C and pushes past 50 under load. It probably isn't much, but I decided to change the thermal paste just in case that was the problem. I used Arctic Silver Ceramique, and followed the instructions on the website EXACTLY... and now BIOS reports ~40C and rising, without any activity at all. What could have happened?

 

[joefriday]

It is summer. You have a 125 watt processor. BIOS runs cpus hotter than windows because there is no HALT state. No need to call Ripley's.

 

[moshee]

The thing is, I noticed the temperature change within Windows to start with. One day I noticed that the temperature was 5C above normal. I changed the thermal paste, following every instruction carefully. Booted back up, and the temperature was even higher. It's just unexpected, nothing too serious, although under load the temperatures can get a bit scary.

also, it's not summer, it's raining and about 50 degrees F outside...

 

[hundredislandsboy]

On computers I use, I monitor idle/load temps on a daily basis and I frequently (monthly) swap CPUs between motherboards for various benchmarking. Each time, I'll clean off the old thermal paste, blow dust off the fans, off the motherboard around the CPU area, etc...

I notice during the first day after a CPU swap, the idle temps are around 3 to 4 C higher from their "normal" or previously recorded idle/load temps. And then after a day, they're back to normal. Could be the Artic Silver 5 settling in, burning in into a nice flat layer and then thermal conductivity improves just slightly?

 

[moshee]

I think I've heard something similar to that, I'll see if anything changes. Thanks for confirming it.

 

[pdusmc]

Artic sliver says on its packaging that it can take up to like 30 day for you to see a difference in temperature so "don't sweat it". Haha PD made a funny