Propably not, the question is how old is your current power supply and which brand? If it's older than 5 years, propably better to get a new one. 700W should be enough for the next 5 years, even when you add in a few extra harddrives or a second graphics card. I'd also suggest looking for a modular one. Also it should have atleast an 80 plus bronze certificate, I'd actually recommend gold. That basically means that the PSU won't fail to supply it's full power even under heavy load, which cheap PSU's usually do. More information here:
http://www.pcworld.com/article/2025425/how-to-pick-the-best-pc-power-supply.htmlI'm currently running with a 380W power supply, however my GeForce GTS450 "needs" 400W, according to nVidia. Been using it now for a few months, no bluescreen, no sudden shutdowns, nothing, works like a charm.
As for a suggestion, I'm not really up to date when it comes to companys, but the usual like Corsair, OCZ and Seasonic seem pretty reliable, according to a quick google search. However, this list seems pretty good to me:
http://www.tomshardware.co.uk/answers/id-1804779/power-supply-unit-tier-list.htmlNever save money on a power supply, think of it like the foundation of a house, if that isn't build properly, the whole house will fall after some time.
