I recently got my hands on a Gigabyte 7870 ghz edition card from a friend. I want to begin overclocking it but need to know what amount of voltage should I stay around? The limit on voltage is 1.3v, is going that high safe for 24/7? If I keep temperatures below 75c would it be fine if I go up to 1.3v? If anyone can answer these questions for me then I would appreciate it every much.