I was wondering if my PSU will be up for any of the two. the specs are
IN 230V 5A 50hz
I'm currently using an XFX hd radeon 4890 (which I understand consumes MORE power, and even takes 2 4-pin connectors) with two 500gb disks and everything works just fine. the system is an AMD fx6100 (x6), mobo ASUS m588a-m, 8gb ram, and a dvd recorder.
would there be a difference in power consumption between the OC version and the non-OC?
yes your psu would handle either of those gpus with ease without any problems. Even at maximum load, your system would only draw around 250w. There will be some difference is powerdraw between the oc and non oc model but it'd be subtle differences.
it's an OverTech PSU. I'm aware it's not a well-known make, but as it runs the 4890 radeon (and I've just opened the CPU and remembered/saw that the 4890 takes TWO 6-pin connectors, while the 7850 only one) with total ease, I figured it would run the 7850 (maybe even the OC edition) with no problems.