PSU Specs

Just a quick check on PSU sizing.

I currently have a Corsair TX 650W PSU which has ran my current setup with no issues for the last two years. However, in the upcoming sales, I am planning a few upgrades. Mainly upgrading my 4870 to a 5970 (or 5850 in crossfire), dropping my raid 0 array (4 x 500gb) for a 80Gb ssd and upgrading my other 4 drives (500gb to 2tb) to a raid 5 array with 5 x 2Tb discs.

I've checked a couple of psu calculators and they all seem to think that the max size of required PSU will be 560Watt. Not sure whether to trust this and stick with my 650W one or to speed even more cash and go higher...

Any recommendations?

Thanks for your help!