Should I be concerned about +5 rail with lots of hard drives?


Jul 12, 2006
I have an 8 year old Seasonic M12-700 watt and I have a rare boot up issue with USB devices that I'm not sure if it's just the PSU is old or something else.

It's rare, but sometimes when I reboot some USB devices won't function, particularly the keyboard. I thought it was a motherboard issue, but this has been going on for a few years and I've replaced the motherboard, keyboard, pretty much everything but the PSU after all this time. And usually if I unplug something from a USB port and reboot it's fine.

The PSU is old and probably due for a replacement anyway, but I want to be sure the new PSU can handle all my hard drives and USB devices. I'm concerned, because my Seasonic had 30amps on the +5 rail and I see most PSUs seem to only have 20 or 25 amps now.

I have (not sure if all this uses +5)
10 5400 RPM hard drives
2 SSDs
4 USB 3.0 hard drives (self powered)
backlit keyboard, mouse, two game controllers
wireless USB headset
7 1450 RPM 120mm fans
fan controller

Other things (assuming these not affecting +5 rail)
GTX 680
i5-4500 @4GHz (stock voltages)
ASUS Z68 motherboard

Do I need to be worried about the amps on the +5 rail on a quality PSU? I'll probably get another Seasonic,
The Seasonic M12II 700W PSU should be fine. You can check your 12v, 5v and 3.3v rail voltages with your motherboard utility software or HWUInfo64 software (Sensors). All readings should be within 0.2v of the target voltage.