As of 1 week ago my computer started having some really weird coil whine coming from the PSU, and my monitor became black a few times and you could hear the GPU fans go 100%, so i instantly went and dusted the whole thing, after that the gpu problem happened again 3 times now, usually about once a day, and when i turned on the computer today, i had to do a disk check.
I've also experienced some random lag on my computer.
the specs are:
GPU:AMD Raedon HD5850
CPU : intel i5 2500K
8 GB Ram
the psu is LC power 550W, they are widely spread in europe.
Any help is greatly appreciated because i think the psu is bad and its damaging all my other components, so i want to act fast, but dont know what to replace or do!
Agreed, first step is going to be to replace the PSU. If it is spitting out bad power then it can cause all sorts of issues. Something like a Seasonic tends to be good quality while affordable, though I am not sure about european availability. Whatever you buy make sure it is rated as 80+ Bronze or better.
Once you have a proper PSU then look into replacing other parts.
on a side note:
You have a K-sku processor and a motherboard with a h61 chipset? You may want to consider upgrading your motherboard. A z68 or z77 based motherboard will allow for overclocking, and they are quite cheap now that they are 'older' motherboards.