Hi I am thinking of upgrading my 5770 graphics car (I have this one its the HIS version), to something better but I dont want anything to expensive £100-150 roughly. My system specs are below, also my motherboard supports crossfire so would it just be worth getting a second 5770 instead of getting another single card?
In some cases less. But with the problems still sorrounding crossfire in many games, the GTX560 would be a lot better in some cases.
I am considering the same as you. you can crossfire a 6770 with a 5770 (since it is the same chip) but the 6770 needs to be "first" in the motherboard due to driver-stuff.
I will probably go for the 5770 crossfire if I can find a used one for about 55eur/£.
EDIT: http://extreme.outervision.com/PSUEngine Recommends about 460watt power supply (with some other stuff thrown in for good measure) so we should both be fine there.
EDIT2: By the way. I would like to know, what voltage did you use to get that overclock? I managed it at 1.26V which makes my max temp around 60C.
and for my overclock my motherboards is really weird so you can not manually change the vcore, it is changed automatically so it runs at 1.33v and I have a big fan which keeps it at about 65 Degrees at full load
You should be able to change the voltage from automatic to manual/fixed or offset?
Either way, if you keep voltage below 1.35V and temperature below 70C you are probably fine. Although lower voltage and temp is always better for longevity.
As I said, the calculator recommended about 460w for systems like yours or mine with 2x 5770. It depends then, on the quality of the power supply (I had a 650W that could not run my system with even one 5770)
Be Quiet is pretty decent I think. I take it you have a Purepower L7 or L8? Those are either 80+ white or 80+ bronze rated. which should ensure at least a reasonable quality. I think you will be alright.
I agree with chinoroy, if you can find a cheap 5770/6770 it can be a much cheaper alternative since you already got one. if not, go for a single strong card, then you also avoid driver issues.
About the CPU: mine is not 100% stable. One time it failed after 2 hours of prime95. another time it was stable for 3. I count that as good enough for a gaming/surfing PC however, and it have never failed while running anything else (including, for instance 15 minutes of intel burn test)