Since recently, I have a problem with sleep mode on my Windows 7 - when the computer enters the sleep mode (S3), all other devices are powered down, but the fan on graphics card (NVidia GTS 250) goes 100% and very noisy. The computer therefor won't power down - the fans on graphics and the power source are running, and the power leds are shining.
Few days ago, everything worked fine - computer was able to sleep (everything powered down, no fans running, no leds shining) and wake up again. I don't remember changing any settings or installing any updates or drivers
that may have caused this.
Now I'm also unable to wake up the PC - I have to disconnect the power (or switch off the power supply swtich) and start the PC, which then resumes the Windows from hibernation (I'm using hybrid sleep mode).
So the problems seems to be in the sleep mode (hybernation itself works ok).
I've googled intensivly found and tried a lot of things, but nothing helped. I tried to change the hybrid-sleep to sleep. At first I even ran a memory tests, because I thought it may be some problem with a RAM module. I upgraded my video drivers to the latest version. I tried to switch the fan control between automatic and manual in NVidia control center. I tried to modify the power plan in power settings and the PCI express settings. I cleaned the hardware from the dust as well.
Basically a lot of people seems to have a problem with fan on 100% AFTER resuming from sleep. But it is not my case I think - unless my PC in fact goes to sleep sucessfully, then wakes up immediately (for some reason) and the fan goes 100%. But the displays stay black and the PC seems not to work (until I power it down and resume from hibernation as described above).
Does anyone have an idea what could be the reason or what else can I try ? Was there maybe some recent windows update, that could have caused this ?
Trying to figure this out I found those threads, but they were not helpful in my case : When computer goes to sleep graphics card overheats GPU Fan at 100% after wake up from S3 - nV News Forums GPU Fan 100% During Boot and Resume - Neowin Forums Max fan noise in sleep mode - PowerMac G5
BTW my HW is as follows :
CPU Intel Core2 Duo E4400 2.0GHz/2MB/800MHz/LGA775
MB Gigabyte P35-S3 Sc 775 P35-S3
RAM A-DATA 4x1GB DDR2 PC800 Extreme Edition
NVIDIA GeForce GTS 250
160 GB hitachi HDD
640 GB samsung HDD
1 TB samsung HDD
LCD Eizo 17'' M1700
LCD Samsung 19"