Will a 550watt be enough for a gtx560

I wouldn't consider a no-name, cheap PSU to be a bottleneck...it's more of a hazard. The bottleneck will be the CPU. What is the make/model of your PSU?

A system with a single GX560 requires a 450W PSU with at least 30A combined on the 12V rails and two 75W 6-pin PCIe power connectors. Will your current PSU work? It will most likely work and you've got a 'known good' PSU; at least one that hasn't failed with your current loads. I never recommend a cheap, generic PSU; they have a tendency to fail and take other components with them when they go. If it has sufficient power on the 12V rails and you are satisfied, then you have to make the call on whether or not you'll use it.

If you need I can check what make it is, but so far it's 3 years old and has yet to fail me (my resolution is 1280x1024 so I doubt my cpu will bottleneck much). it isn't the cheapest PSU (i think) it's just not a well known branded one. it's late at the moment so I would rather not check but I will If you think I should.

No rush - check it later and post at your convenience.

DO NOT I REPEAT DO NOT Get a cheap PSU.

I was once at a friends house after about 2 weeks of getting his new rig. All fancy components, nice new i7, gtx 560 ti, 8gb ram, the lot.. guess what happened. Playing some world of warcraft for about 3 hours. Next thing you know, BANG, yeah the processor and gpu got tooken with it and would no longer work. I seriously don't recommend getting any cheap psu without 80+ at the risk of losing the rest of your components  

Get a PSU from Corsair, Coolermaster, and Antec. All excellent Power Supply Brands and comes with a good 3-5 year warranty.