I've recently upgraded my graphics card to a shiny new Powercooler 6870. I've been using MSI Afterburner to monitor the card temperature and load to make sure everything is Ok with it, and I've set up a temperature profile to automatically adjust the fan speed depending on what temperature the card gets to.
Everything has been OK with it, but I've started noticing some strange data showing in the Afterburner monitor. With no games running, typically when browsing the web, the card temperature sometimes gets into a state where it cycles quickly between around 40 and 46 degrees. Its normal idle temperature seems to be around 39. I wouldn't normally worry about this, but the speed with which it is doing so seems too fast, particularly when it jumps straight from 40 to 46 degrees without any intermediate temperatures. It makes me worry whether the temperature reading is accurate. The image below shows what I mean. As you can see, it sometimes stops cycling between the temperatures by itself, but other times it can do this for hours.
I was wondering if anyone can shed any light as to whether I am being paranoid here, or whether the stuff I am seeing points to an underlying problem with the card.
Run HWMonitor http://bit.ly/pXcS5g see if the same thing is happening in this application. If it is, maybe something's messed up with your readings, but as long as it's still in the same range you should be fine (ie you're probably not in danger of your card overheating or anything).
If anyone's interested, I've rather embarrassingly worked out what is causing this.
It seems that Steam uses hardware acceleration, and when it is on its main store page with the sliding main image at the top, it uses hardware acceleration every time it slides, even when Steam is only running in the background.