Mar 13, 2012
I just built myself another new computer, but I'm having trouble with the drives. I have an OCZ Agility3 60 GB drive for 64 bit Windows 7, brand new Western Digital 2 tb and 3tb drives, and a Hitachi 500 gb that I wanted to use for backup. I also have 2 DVD burners. My problem is that no matter what I do, I can only have a total of any three of those drives hooked up in any combination or else everything but the OCZ loses power. I have a 700 watt NZXT power supply that was running my old computer very well, so I thought it was plenty of power, and wouldn't be a problem to put it in the new system; but it's the only thing I can think of as being a potential cause for my problem. I can attach a drive through a USB port, and that doesn't cause anything to lose power; but that does draw its power from an outside source.

Oh, and the rest of the computer is an Asus p8z68-v/Gen 3 motherboard, an i7 2600k with a CM Hyper212 EVO with 2 fans on it, 8 gb memory, and a 560ti. I have a second 560ti I would like to put in, as well as do some overclocking; but I didn't want to do either until my power issues were solved. There are also 5 case fans going, although that's without the door that has 2 more on it attached. I'd appreciate any input on if the power supply is actually the cause or what else it might be.
My est of your power is ( loaded by running furmark) is approx 350 Watts + 30 Watts for additional HDDs. This is well under the 700 Watts. If your having power problems then Your PSU is either poor quality, or is failing.

My System: i5-2500k OCed to 4.2 w/ 6860 GPU, 2 SSDs, 1 1 TB HDD, one Blu-ray writer, 16 Gigs of DDR3-1600 Ram. My Power consumption at the wall is 350 Watts.

What I would do is measure the +12 V rail. Min voltage is + 11.4 V (I use 11.6 V as a min value).
.. Preferably with a Digital Voltmeter, They are cheap (about $15 @ walmart) and very easy to use (Just google How to use a voltmeter (some excellent you tube videos). You can measure the +12 Very easily by inserting the Red meter lead into a molex connector Orange (or yellow) wire for the +12 V (red wire pin is the +5 V) and insert the black meter lead into the Black wire pin.

.. Alternate method is software. If you have a motherboard utility that displays the Votages use that. There are others such as HWMonitor - BUT if it shows say <10 or >15 then it is not reading correct. I believe speed fan also displays voltages.

With the above and one HDD connected: (A) check at idle, then run say furmark, or prime 95, to load the +12 V rail. Then (B) repeat by adding aditional PSUs.

If (A) is OK but (B) is not then; You may be loading a single rail (multirail PSU) above its rated Rail limit. This is not a problem with a single rail PSU.
If the +12 V dropps 0.3 V, or is below 11.6 when loaded - DITCH the PSU.

ADDED: A Digital multimeter (DVM) is VERY handy around the House and car - Not just for Computer/electronics.