from Lenovo. cpu i5 2.5 mtz about $600.
I have used it for two years without problem.
http://shop.lenovo.com/SEUILibrary/controller/e/web/LenovoPortal/en_US/builder.workflow:Enter?*****=%3A00000025%3A00002DD9%3A&smid=9E9C59AB7E14CD865AA41873FE087F72