Computer fans only move when a SATA power connector is plugged in (You read that right!)
Ok i've been investigating a problem here. My pc has degraded over the last month. I.e. Taking more attempts to successfully POST. Now it never POSTS, beeps, displays...
The fans move and there is HDD activity.
However i've played around and found that if i unplug the HDD power, the PSU fan and CPU fan stop moving after a second. With the HDD power cable plugged in the fans resume moving.
I noticed a slight thing with the CPU fan. With the HDD power plugged in. Where the CPU fan would usually stop spinning after a second, i can see it slow down slightly but picks up speed and carry's on due to the HDD being plugged in.
NOTE: I say HDD but the fans will move with any SATA power connector being plugged in.
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Possible PSU problem or there is something wrong with the motherboard.
Well i tried another PSU and the same happens except no SATA power connector is needed to keep the fans moving. It still doesn't POST. Maybe am unlucky and both PSU screwed.
Try the board on the outside of the case. If that still does not work, then it's the motherboard.