Windows System becomes Jerky/Stuttery after prolonged use

This is driving me mad. I run Windows 7 Pro 64, I've been running off the same install for the last couple/few years. I keep my system clean (hardware/software) and it runs everything fine... However, when it's been on for 8-10+ hours I notice that YouTube video becomes slightly laggy.. and i get frame rate drops in game..

So I started using the frame rate command in BF4 to monitor this, I play 1440p maxed out and get 70-80fps, I'll notice that every 5-6 seconds the frame rate drops by almost half for a single frame then returns. I get the same issue regardless of the game/app running.

I've looked at the Task Manager whilst gaming to see what could be hogging resources and nothing jumps out at me. It's been like this for a while now and a simple reboot solves the issue. I reboot then load back into the game and it's like butter.

My rig is running 4 monitors (3x22" 1080p 1x28" 1440p) my system is stable and for the last 6+ months it's been running at stock. I have a slight OC on my Titan (resetting to default doesnt fix) and have the lasted drivers and updates installed.

I've tried CCleaner to clear out the REG (after so many years running the same install I thought for sure this would be the problem) and ran other apps to clear temp files and the like.

Yet it still becomes laggy after prolonged use. My temps are great too, I'm totally at a loss as to whats causing this.

Any ideas?

SPECS:

Hardware-
Silverstone ST1000 1KW PSU
Asus Maximus IV Gene-Z GEN3 MOBO
Intel i7 2600k @4.5ghz
Asus GeForce GTX Titan
Asus Xoner DX2
2x 4GB SAMSUNG GREEN DDR3 @1866mhz
OCZ Agility 3 240gb SSD (Games)
Plextor M5 Pro 256gb (Windows)
Seagate 3TB Barracuda (Data)

J.

 

It's worth downloading a boot time malware scanning CD just to be sure you've got no naties lingering on there.

 

I use NOD32 which runs a startup check before Windows loads applications, though I can see the flaw in that. I know Avast has a BOOT USB feature. Can you recommend one?

J.

 

Bitdefender rescue CD. Will scan your entire system whilst its offline. Great little tool.

 

+1

 

Well that didn't work... :-(

J.

 

Trying ESETs variant..

J.

 

Bit defender quite often does that. It generally boots in after a fw minutes

 

Oh bugger... I just bailed on it after 30 seconds and made a the NOD32 boot USB thang instead.. Grrr

J.

 

if its a virus or malware, try hitman pro (3)

 

Get a copy of Process Hacker it's a lot more detailed than task manager and will show you just what processes are running and what resources they are using.