Detecting keylogger

Hi,
I am not sure whether a keylogger is installed on my pc. I suspect so because the settings on my KIS 12 were not set to detect keyloggers ( not sure how, but I'm not the one who chaned the settings?). my laptop was hacked a while ago, though I formatted my pc, the hackers still have info about me (the specs of my pc, it's name...). A full system scan shows nothing, but what if the keylogger was installed while KIS settings were set not to detect it? What can I do in this case? Plz help
Thank you.

Most harmful software disables anti-virii as a whole, rather than JUST keyloggers. I don't mean to make you paranoid, but if you do find a keylogger you might want to consider who else within your house has access to your computer.

First, thank u guys for responding....second, sorry to be late to reply

Flatiron: scanning my pc with both programs came out clean 100%

How do I know that my hackers have my personal info?
Well, they re-named fb accounts with my real name & pc name. The problem is my cousin was the one who blogged on their website from my pc while I was abroad. After conducting a full system scan 3 weeks later, I found 15 Trojan programs that were downloaded 3 weeks earlier.
I believe that my pc was hacked because had they hacked her fb account only, they could have learnt about my pc specs from fb security tab, but not my real name or pc name. Even after formatting& re-naming my pc with the weirdest name, they renamed a fb account with my new pc name???
Thank u guys,