System Running Slowly

[jayviper800]

I Just built a new PC the specs are
i5 2500
asus p8z68-v lx
8g(2x4gb) corsair vengeance (CMZ8GX3M2A1600C9)
corsair 650W tx PSU

I reformated my old harddrive and put a fresh Windows 7 64bit home on it. My system boots up just fine, but as soon as i log into my windows profile it lags big time loading my desktop. From there every program i click on lags a good 2-5min before opening. All my hardware is being registered through both windows and my Asus probe program. However my RAM is not listed on the mobo's qualified vendor list. Could that cuase my system to be running as sluggish as it is? or is it perhaps another issue?

Thanks to anyone who can help

 

[jayviper800]

PS. I ran check disk, system mechanic, and antivirus software.

 

[Outlander_04]

what hard drive and how old?

 

[jayviper800]

its a Western Digital 250gb SATA, and i think its about 5-6 years old if memory serves. it was originaly running xp on my old mobo/cpu combo(asus P5WD2 / p4 3.2ghz) last week, and it was running smooth.

 

[Outlander_04]

have you tried reinstalling windows?

 

[jayviper800]

Yup, i reformated my harddrive and reinstalled windows yesterday.