System uses about 400W under no load with 50% of the cooling system turned off. I can only simulate 160W of load using the cooling system from a 10 year old system on the suspected bad psu but so far can not find anything wrong with it despite the fact that swapping it out has for now resolved my problems in that I can run furmark with no issue.

These psus are all pre ocz. The 750W I am using in here now is about 8 years old. Did not even have an 8pin gpu connector as I had to use a dule 6pin to 8pin adapter.