how do i check? im gonna get 1 3pin fan, and 1 4pin molex fan, but how do i check the temperature?
Get MSi afterburner. it is a great tool for fan profiles to keep your GPU temps cool, and monitor all data usage/temperatures for the card. It also is an overclocking tool if thats your thing. I tend to try and keep my GPU temp around 70-73ish if that helps at all. The 5770 should run fairly cool as it doesnt need much power. If you have a reference model, your case shouldnt get too hot - you will need fans, but it should be too bad because the reference design has an external case exhaust for the GPU.