Games Suddenly Choppy

[Lord Camel Balls]

Yeah...

For some reason, all games on my PC have become really choppy. Everything was running flawlessly yesterday, but today I tried booting up Arkham Origins, and I could barely make it passed the main menu. Even response time from my 360 controller was slow. I tried some other games, and the same thing. Anybody have any idea what might cause this, and know how I could go about fixing it?

Also, streaming video from Youtube and such has been choppy as well today - if that helps narrow it down at all.

My set up:
Intel Core i7 2600k @ 3.40GHz
ASUS Sabertooth P67
GeForce GTX 580
16 GB DDR3
Win 7 Home Premium x64

[Astartes]

It is probably something running in the background. I would try rebooting first. If the problem persists, check Task Manager.

[Lord Camel Balls]

I've already rebooted, and the problem persists. I've checked the task manager, but I really don't see anything that stands out.

Here's my tast list. I'm not really sure what's there that's unusual.

System Idle Process
System
smss.exe
csrss.exe
csrss.exe
wininit.exe
winlogon.exe
services.exe
lsass.exe
lsm.exe
svchost.exe
nvvsvc.exe
nvSCPAPISvr.exe
svchost.exe
MsMpEng.exe
svchost.exe
svchost.exe
svchost.exe
CTAudSvc.exe
svchost.exe
svchost.exe
spoolsv.exe
svchost.exe
armsvc.exe
AppleMobileDeviceService.exe
mDNSResponder.exe
HD-LogRotatorService.exe
IPROSetMonitor.exe
NvNetworkService.exe
nvstreamsvc.exe
PDFProFiltSrvPP.exe
PnkBstrA.exe
SavevidService.exe
WLIDSVC.EXE
HD-Service.exe
WLIDSVCM.EXE
HD-Network.exe
conhost.exe
HD-BlockDevice.exe
conhost.exe
HD-SharedFolder.exe
conhost.exe
WUDFHost.exe
svchost.exe
wmpnetwk.exe
SearchIndexer.exe
nvxdsync.exe
nvvsvc.exe
nvstreamsvc.exe
conhost.exe
dwm.exe
explorer.exe
taskhost.exe
NvBackend.exe
msseces.exe
StikyNot.exe
uTorrent.exe
SystemWhileIdle.exe
Dropbox.exe
Ctxfihlp.exe
pptd40nt.exe
pdfPro5Hook.exe
BrStMonW.exe
jusched.exe
BrCtrlCntr.exe
BrYNSvc.exe
SavevidWSServer.exe
SavevidPluginCore.exe
nvtray.exe
CTxfispi.exe
svchost.exe
BrCcUxSys.exe
dllhost.exe
wuauclt.exe
chrome.exe
chrome.exe
taskmgr.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
svchost.exe
dfrgui.exe
chrome.exe
chrome.exe
chrome.exe
AvastSvc.exe
AvastUI.exe
Steam.exe
SteamService.exe
cpuz.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
chrome.exe
msconfig.exe
chrome.exe
cmd.exe
conhost.exe
taskeng.exe
SearchProtocolHost.exe
SearchFilterHost.exe
tasklist.exe
WmiPrvSE.exe

[Astartes]

Sort taks manager list by CPU usage or memory usage.

[Lord Camel Balls]

Thank you. It seems SystemWhileIdle.exe was the problem. I've never seen it before today, and once I killed the task, games and Youtube videos seemed to go back to normal.