HDD light always on, slow boot

hi guys
I recently experiencing a serious problem with my laptop (Sony-vaio Z720D)
it has became very slow and system startup takes too much time (about 7 mins), after starting up, HDD light is permanently on and system is very slow for about 30 mins and then it comes back to normal. i checked the running processes from task manager but there's nothing to do with them, also startup programs aren't taking too much memory. my function keys are not working except for volume control. i am pretty sure that there's no virus in my system, i checked it with my antivirus (nod32) and microsoft security essentials. i also checked my c drive with CHKDSK it could'nt find any error related.
So i'm disappointed and i would appreciate if anyone can help me
Thanks

Disk drive model is : Hitachi HTS723232L9SA60

I also performed MBAM quick scan which led to results below

Memory Processes Infected: 0
Memory Modules Infected: 0
Registry Keys Infected: 0
Registry Values Infected: 1
Registry Data Items Infected: 1
Folders Infected: 0
Files Infected: 2

all the infections cleaned successfully by the way

i ran sfc /scannow from cmd and after verification and taking some minutes it said "windows resourse protection found corrupt files and successfully repaired them" and wrote them in cbs.log

then i restarted my system but things are much the way they were before...

Time to try Clean Boot Troubleshooting whereby you disable nonessential services to see if the problem goes away, and then re-enable little-by-little until the culprit is found.

i performed clean boot and disabled all non-Microsoft services but HDD light is still on and system spped is low. function keys aren't working either

I think you might want to run some diagnostics on your hard drive. It could be failing. You should be able to find what you need on the hard drive manufacturers web site.

Quote "i checked it with my antivirus (nod32) and microsoft security essentials"

Are you running Eset and Microsoft Security Essentials at the same time?

Try running some S.M.A.R.T. monitor tools found here: smartmontools

Run the following commands in Windows:

Code:

smartctl -a /dev/sda | more

That may be a bit TOO linux like but the command for Windows is something like that. Find anything you can find that may seem a bit out of the ordinary, including any S.M.A.R.T. errors listed towards the top of the output.

Good luck!