So im shopping for all the parts for my first computer build, I did one of those things were they calculate how many watts your computer will use I got around 600w and I saw a 650w and a 725w which one should I get or should I get a higher PSU? thanks
It's always good to go above, for future additions in terms of hardware and if you may want to overclock and whatnot. Make it more future proof go with the higher wattage.
If you aren't going to update your rig in the near future buying higher wattage PSU will be only a good thing after you will pay the eletricity bill. Line up here what you'll be buying and we will see if it really gonna "eat" to that 600W.
Wattage isn't nearly as important as the amperage. The more amperage on the primary 12V rail, the better. It's best to have a PSU with a single 12V rail. I got a 750w which I thought was a killer deal at the time, but it has 4x 12v rails, each around 20amps, which means I will likely run into trouble with some power hungry GPU's, esepcially in CFX/SLI, as well as extreme overclocking, despite having ample wattage. I haven't run into any issues yet, but I'm not really torturing my PSU either. I have a 2500K @ 4.5GHz (1.325V) and a stock Radeon 5830. I'd be in better shape for OCing and GPU upgrades I had 40+ amps on my 12V rail.