Hi. A while back, I put in a new video card (Nvidia Geforce GTX 560 ti) and installed the drivers for it. Thereafter, I started to see huge spikes in cpu usage that would cause my mouse and everything on screen to lag, as well as the audio (for example,
if a sound was playing when a sudden bout of lag would hit, it would repeat the bit of sound that it was on when the lag hit repeatedly and very rapidly. It sounds like a machine gun is going off.)
I tried doing clean installations of the drivers and even went back to the old graphics card, and none of that helped. I inspected the running processes whenever a sudden bout of lag would hit and none of the processes seemed to take up an exorbitant amount
of memory. Finally, I did a fresh reinstallation of Windows 7, and that seemed to solve the problem.
Fast forward a few months. I haven't done any windows updates since I reinstalled Windows 7. I've been getting this curious, but apparently very common, problem where when I saved something in an application (any application, from explorer to Chrome) the
application would freeze for a while if I created a new folder. I decided to run windows updates to see if maybe there was a fix for this. As it happens, one of the updates was a service pack (SP1). After installing the service pack, suddenly I'm having these
same lag issues again, and it's making my computer entirely unusable.
So, more details on the lag:
1. Causes CPU usage to spike from around 20% to 50% (I haven't had a chance to test it when the CPU usage was higher than around 20%) and I've seen it go up to almost 100% before.
2. The spike occurs across all of the cores
3. The spikes are not independent incidents: when one happens, they keep coming, separated by one or two seconds at most, for several minutes, sometimes even up to 15 minutes.
4. However, there are sometimes long bouts of time where, despite nothing being different, there are no spikes at all.
5. Putting in my old graphics card does not fix the issue
6. The spikes cause both visual and audio lag.
7. The spikes can occur when I'm doing just about anything, from browsing steam to running a browser or using windows explorer.
My PC specs:
Processors: Intel Core 2 Quad CPU QR300 @ 2.50 GHZ x4
RAM: 8 GB
Graphics Card: Nvidia Geforce Gtx 560 ti
OS: Windows 7 Service Pack 1
And finally a picture, showing the task manager performance tab and the resource monitor at the time of a long series of spikes: http://i.imgur.com/dpGIT.png
Here's a list of things I have already tried:
* I have performed clean installations of freshly downloaded video drivers from the Nvidia and Geforce websites, three times over.
* I have used sfc /scannow to check for problems with core system files.
* I have run scans for malware using MalwareBytes Anti-Malware
* I have switched back to the old graphics card (didn't fix the problem) and then switched back to the new one again (also did not fix the problem)
* I followed the instructions here: http://blogs.msdn.com/b/davidnotario/archive/2005/04/27/412838.aspx for getting rid of mscorsvw.exe in case that was the
issue (it wasn't)
* I have used older drivers for my card in case the issue was with the newer drivers
* I have performed a clean boot with no services other than Microsoft services running and no startup programs (still got lag after I did this).
Any help would be greatly appreciated. I haven't the slightest clue what is causing this, and I'd really like to have a functioning PC again. Thank you.
Edit:
I've been vigilantly watching the process manager and resource monitor every time I start getting spikes, and I've noticed a pattern. Every time I start getting spikes, the Process "System Interrupts" jumps up to the top of the list of processes when sorted
by CPU, and its CPU usage goes from less than .5 (which, as I understand it, means .5% usage of the CPU) to 9 or higher. None of the other processes show any change in CPU usage, just that one.
