Computer randomly gets a blue screen

Hi there.

Few days ago I connected an old hard drive (not really old) that always worked upon connecting (I connected it over 5 times this month, at least) I disconnect it mainly because I don't want it to be effected from viruses or anything, I got important stuff there.

It's not an external hard drive, I had to open my pc case to connect it of course.

After connecting it my PC suddenly didn't show anything on screen, so I said ok, something is probably wrong with this hard drive (didn't find a solution to this) and decided to disconnect it.

From that point I kept getting random blue screens on my PC (I have this PC for 5 years and I never, NEVER had a blue screen, not even once.)

The blue screen said that I should remove any new installed hardware (which was probably my old hard drive)

and wrote

*** STOP: 0x0000003b (0x0000000c0000005, 0xFFFFF80002ACAF92, 0xFFFFF8800AD47AD0, 0x0000000000000)

Didn't really count the last with many 0 on it.

I tried playing with my RAM memory and somehow ended with both connected but having 2GB instead of 4GB (I put them back into their original places)

I currently run safe mode with networking but it gets this blue screen after maybe 15 minutes when on normal mode I get this after between 10 seconds till 5 minutes.

I noticed that opening Steam or xfire immediately gave me this blue screen so I deleted both from my PC but I still get this crash after few minutes.

my PC specs are:

Proccessor: E6600 Dual core 2.4 Ghz

Memory: 4GB 667Mhz (now got 2...)

GPU: GTS 250 1GB

Windows 7 64bit

Is there a way to fix this blue screen problem and connect my old hard drive again? it's currently connected to my PC but doesn't show on "My computer".

via Bleeping Computer Last 20 Posts http://www.bleepingcomputer.com/forums/t/509434/computer-randomly-gets-a-blue-screen/