Psu problem



Hi, I have an Alphapower 850w psu in my current system which has a hd4870 the psu has provided trouble free service for me, the question i have is i am planning to upgrade my system to a Msi k9a2 Platinum, Amd Phenom 9950 and an additional hd4870 to work in crossfire i am on a tigh budget and havent really got the cash to buy another psu so was hoping this would be suitable, if it is the psu has two dedicated pcie 16 power conectors i would require another two, can i use the molex connectors with pcie16 adapters?
Yes, you can use two adapters to provide the missing PCI-E connectors.

850W is well above the minimum 600W recommended for HD 4870 Crossfire, so you shouldn't need a new PSU.