Computer suddenly went Extremely slow

AsadHabib

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Nov 6, 2013
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Ok so i have this pc

i7 2600k (never tried ocing)
8gb corsair ram
1tb hdd
asrock extreme 4
psu corsair hx520
gpu saphire 7870 2gb
win 8.1

the problem is i bought this system over a year ago and it flies. never had any problem or anything. i usually am not home cuz i go to college and come back on weekends. About 2 weeks ago i left this pc smooth and running as always. but now that im back its Extremely slow. like i can even get my games to open. the whole windows / system has slowed down. my sister uses my pc sometimes she says she tried installing c++ and thinks she mightve inflicted my pc with a virus so i scanned my pc = no result. re installed windows scanned again its fine. but after restarting a couple of time , all of a sudden its extremely slow once again. like even now when i type the letters appear after some time. Please help me out im gonna try cleaning and replugging things in the meanwhile.
 

AsadHabib

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Nov 6, 2013
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thats the trouble i dont have a restore point all the way like 15 days back. Thing is installed a fresh copy of windows so that shouldve solved software related issues right? but even like right after i opened windows for the first time it was like that again.

Ps i just opened up my system, cleaned everything, unplugged/ replugged everything, blew into holes and stuff, etc. Its fine uptill now... i hope it stays this way. will update soon.
 

menetlaus

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Jul 19, 2007
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There are some bad pieces of software out there that can get into a motherboard/USB drive/printers/etc and re-infect a system following a HDD format and reinstall.

You may want to eliminate all unnesessary connections (scanner, printers, etc) and try a virus/malware scan using a linux live CD (aka scan the windows drive, USB drives, etc from within Linux). This way if a virus is so deep into windows that you cannot see it from a windows virus scan - it might not be able to hide from a completely different OS running off a DVD.
 

AsadHabib

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Nov 6, 2013
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No i havent done that. Could you recommend me any free softwares?
Ps i cleaned up my cpu from the inside replugged stuff so its fine now. But i have a feeling this wont last.