high average load and internet loss

[AngelDeaD]

About 10 days ago i got problem with few proccess:
migration/1
migration/2
migration/6
kworker/0:2
ksoftirqd/0
ksoftirqd/1

Sometimes they taking about 70% of cpu (according to top)
4 days ago was debain 6 sqeeze, i decide to do something about it. (it's not localhost, it server in datacentar) I send email to support to do full hardware test, after ~10h they reply, everything is ok.
I backup my files (~104gb) reinstall server to fresh new debian 7 wheezy
Server performance:
intel i7 920
8gb (not sure what MHz)
600gb hdd

then i take back my files (into /home folder, where they were).
and problem is still here. I was google about this problem, someone says, hdd is damaged, otherone you are under DDoS, otherone you have an USB attachmed to server... and so on...

Since they did hardware test, and it's good, i think only left is something about my files.
I download, apf, bfd, ddos defalte and rootkit
I set it up, and run rootkit... he found few errors (log file in attachments=115kb)

Thanks in advance for help.