Further info on my setup is as follows:
1 Cube
1 Corsair CX600 PSU
1 Win 7 64bit about a year old Laptop acting as the proxy WIRED to a netgear router
Using the latest version of proxy miner found here
http://mining.bitcoin.cz/mining-proxy-howtoPSU is fine so its just unlucky. Although, are you using two PCI-E cables from DIFFERENT strands of cables?