My PC currently has 7 instances of svchost running in processes, 4 in System, 2 in Network Service and 1 in Local Service. One of the System ones occasionally starts to run up and take all the CPU resource, probably for about 5mins but the PC becomes unusable during this time. The only programs I had open this time were Explorer7 and Media Player 11. I use Win XP home. Any way of telling what this instance of svchost is doing in this time?