About 3w ago, I started to have big slow down when playing games (random freeze and so on). After a lot of researches I found that the issue could be the PC was too hot. So I decided to clean it up and remove the thick layer of dust inside.
I carefully used a vacuum cleaner with a brush to remove the dust from the HDD, mobo, gpu etc... I also tried to clean the CPU fan, but unfortunately, when removing it, the CPU came with it (so i didn't have the chance to lift the lever to properly removed the CPU - which wasn't of my plans but anyway) as it was "glued" to it because of the thermal paste. I put everything back, restarted the PC and ... nothing. All fans and HDD are spinning, but nothing is displayed on the monitor. I briefly smelled a light smell or burnt and immediately switched the PC off. I took the CPU off again and realized that when putting it back in the socket, I wasn't careful enough and I broke 4 pins.
So I ordered a new CPU last week, this time I managed to put it carefully back in place (I read the manual in advance this time), restarted the PC and again, no video signal whatsoever. Everything is starting up (I can see all fans and HDD spinning, all leds seem to show some kind of activity), but nothing is displayed. I know the monitor is OK because I've tried with my laptop.
Again, after some research, I've been told that I probably burnt my MB because of static electricity; so I bought the same MB on eBay, I tried it last week and it still doesn't work. I've re-connected all components carefully and so on, verified jumper settings; but I get no POST message at all. All fans and leds are on, but no POST. So after some thought I ordered a new power supply as I thought I burnt the other on. I've installed everything and it's still the same issue.
I borrowed another graphical card and RAM from work. I've tried one by one all 4 RAM modules (also in different slots), the 2 MB (my old oneand the one from eBay) and 2 graphical cards (both DVI with a DVI-VGA adapter - does it make a difference for POST? I hade that before and was getting all POST messages). The problem remains. I don't know what to do.
The CPU is brand new so it's very unlikely to be the cause of the issue.
I've did all my tests with all components outside the case to avoid any short-circuit.
Any idea/advice is welcome.