I recently upgraded by video card from a radeon 4850 to an nvidia GTX 560. On making this change, my PC began to randomly shutdown, the source of which I quickly identified as the CPU overheating beyond its 'safe' temperatures.
The CPU is an i7 920 c0 stepping in an MSI X58 motherboard.
After some testing back and forth, swapping out the new card and the old one and testing various temperatures, I have the following information:
Old Radeon installed:
Idle GPU temp: ~65 degrees C
Load GPU Temp: ~80 degrees C
Idle CPU temp: ~35 - 40 degrees C
Load CPU Temp ~60 - 70 degrees C
New GTX 560 installed:
Idle GPU Temp: ~20 - 30 degrees C
Load GPU Temp: ~50 - 60 degrees C
Idle CPU Temp: ~50 - 60 degress C, or higher (fluctuates a LOT)
Load CPU Temp: Climbs rapidly upon use of most applications particularly games, caps at around 100 degrees C then the system crashes.
I've been reading forums and doing web reseach trying to find users with similar problems, and I believe I found a few, but for the most part people seem to think that the change is attributable to an overall case temperature change.
My arguments against that would be:
1) Overall case temps causing a 25 degree + swing in CPU tempatures seems pretty extreme.
2) Why would the new GPU running at lower temperatures compared to the old GPU, cause such a huge swing in case temps?
3) The case is a clean and well maintained full tower with 5 correctly configured fans.
Does anyone have any other ideas why this might be happening?
For 1 reason or another the new GPU must be affecting your airflow in a seriously bad way. Where are the fans and which way are they blowing? Also what PSU do you have? Have you gone back to the old GPU to check that it is the problem as you may have knocked the CPU cooler or its fans while installing the new card.
My guess, and I emphasise that it's a guess, is that the new graphics card has a more efficient cooler, which is moving heat out of the GPU more effectively than the old one (hence the lower GPU temperatures) but is moving it into the case, rather than exhausting it from the case.
Some cards blow the heat out through the back panel, some blow it into the case.
As Simon12 suggests, it's also possible that the new card is disrupting the airflow.
You have 5 case fans. You may be able to improve matters by altering the direction of flow of the fans. In particular, I'd make sure that any back panel fans are exhausting air from the case. If you have any side panel fans, you might want to experiment with the direction of air flow for them.
Yes the CPU heatsink is just fine, I trpiple checked and I have indeed gone back and forth between the two cards a couple of times each now to confirm that the results are consistent - they are.
I've posted on a couple of other forums asking for help as well, and as I mentioned in the OP, most folks seem to think as you do - the new card is exhausting heat into the case and causing some serious issues. (It is indeed an open GPU cooler/heatsink and exhausting aggressively into the case, GPU temps are great -_-)
Thanks again for your input - I'll be experimenting with case airflow and a new CPU cooler (I am only using stock currently, a new one may help a bit) in the next few days, and will post an update if successful.