I'm looking at a laptop for a colleague which is running terribly slow. A quick look showed that the CPU was 100% used by 2-3 SVCHost processes, which off course doesn't tell much since those are just 'cover' processes with services running underneath them. So I fired up process explorer in hopes of finding a shady rogue service which was bogging the system, but to my suprise I found genuine MS Windows processes (or at least damn-good disguised ones) are bogging down the system:

• dnscache (DNS Client)
• IKEEXT (IKE and AuthIP IPSec Keyring modules)
• iphlpsvc (IP Helper)

Seen separately, these processes might seem odd to be using a lot of CPU, but taking a step back one can conclude that all three services are quite closely related to networking. I've tried running:

netsh int ip reset log.txt

which has helped me save bizarre network-related problems in the past, but this didn't help Off course I though about a virus, but both MS Security Essentials as well as malwarebytes (let both run a full scan).