You need to do some diagnostic tests first, to figure out where to begin.
You can do hdd drive test to see if that is near failing for starters.
You can check the Windows logs for Applications and System to see if there are any errors being logged
You can check the Performance monitor to see what is taking up so much cpu
After going through all of that, get back with anything suspicious.
Asus Maximus V Extreme BIOS 1903, see specs above avatar.
Asus G73 jh A1 laptop, BIOS 213, vBIOS OD2, 8 GB Ram, 240 GB Intel SSD, 180 GB Intel SSD. Win 7 Pro. Purchased new from PowerNotebooks.com in May 2010.
(both have 1920X1080 hd screens, mine above, hers below )
Asus G73 Sw XR1 laptop 8 GB Ram, 160 GB Intel SSD, 80 GB Intel SSD. Purchased used >Ebay 1/10/13, Did clean install of Windows 7