I have an older machine thats served me well over the years. The other night, it overheated and shut down. After unplugging it and opening the case, I realized the fans were badly in need of a cleaning, and I spent the next half hour or so doing just that. In the cleaning process I removed the fans to blow them out from the other side and really get EVERYTHING out of them. I then carefully replaced them.
Now when I try to boot up my machine, the fans start to run for about a second and then they stop and everything seems to just stop trying to run, however the power indicator light around the power button stays lit.
I was thinking it might be the power supply, but I don't want to go fucking with things without some other opinions.