Hi, even though a have a lot of experience building and repairing computers I never overclocked before, I build a PC for a friend and I build a Core 2 Duo E4300 with an ASUS MOBO: http://www.newegg.com/Product/Product.aspx?Item=N82E16813131041 I Overclock it using the ASUS Bios, I know Core 2 Duo are very reliable for overclocking, but I don't know how safe it is, I just overclock by 10% to reach 1.98Ghz, and temps don't seem to raise too much. I believe she will be ok, but I'm wondering how can I know how far can a CPU be overclocked, ASUS Bios tops on 30%. I just want to hear some opinions about this, Sandra Benchmarks seems to improve a lot when I did the overclocking. BTW I put this RAM on it: http://www.newegg.com/Product/Product.aspx?Item=N82E16820145527 She don't game at all, she only need a fast computer for accounting at home and some other basic stuff. Thank you all beforehand for your input.