I need help to choose between: Chieftec APS-500S, 500W, two +12V rails at 18A or Silverstone Strider Essential SST-ST50F-ES, 500W, one +12V at 34A ????????????????? The computer is meant for medium playing. Other components will be: AMD Phenom II X4 945 nVidia GeForce 8800GT Kingston ValueRAM 2x2GB DDR3 1333MHz Asus M4A77TD AM3
The reason there are increasingly more and more multiple rail PSU's is because it provides for more stability, since components drawing power from the 12v rails do so at different rates. The rails will allow for a balancing of the power draw to guard against a rail being overwhelmed and shutting down. As long as you buy a quality PSU, single versus multi-rail makes no difference. I would go with the Silverstone Strider 500W.
The Silverstone is the better unit, but are these the only two options? A Corsair CX 400W would be a better choice.
Multiple 12V rails are just to save money...it is cheaper to make 2 20A rails than a single 40A rail. If your voltages are dropping or rising on any of the RAILS, there is a problem!
Nope...that is why single-rail PSUs tend to me more expensive. My current PSU has 4 12V rails because that was a whole lot cheaper than making a single 80A 12v rail.
Typically, single rail PSUs are cheaper than multi-rail PSUs but that's presumably because they are also modular. With top end PSUs, it's less a case of cost I expect, more that the scale of making a single rail with such a huge current limit isn't cost-effective. With lower wattage figures I don't expect there's much to be gained from using multi-rail, as surely more components are required.
