A lot of strange noises are coming from the hard disk, but a broken hard disk shouldn't result in stopping after half a second.
This can be an issue with the motherboard or anything on it (CPU or RAM). Your task (or that of the tech) is to find out which exactly. The CPU surely is a candidate.
But just as well it's possible you made some error or damaged something when putting it together again.
Kees
Hello! This is my first post here. I have an issue with my pc and i decided to write here. Today I heard a strange noise, probably from a fan so I powered off my pc and I tried to clean it from dust. After the cleaning I built it again as before and i pressed the boot button. It worked for half a second and then nothing. I changed the power supply, i removed my grphics card and rams and the little battery on motherboard but still the same problem. Is there any possibility for my CPU to have been broken (overheated)? By the way the temperature was good (about 47 oC). Maybe the strange noise was from the heatsink. Sorry for my english.
System info:
motherboard: GIGABYTE Ultra Durable 3
RAM: 2 x Corsair XMS3 DDR3 2Gb 1600MHz
Graphics card: NVidia GeForce GT 440
CPU: intel core i5 (4 cores i'm not really sure)

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