For testing this 600W power supply we installed it in one of our Ubuntu test systems with an Intel Core i7 920, CSX 3GB DDR3-1600MHz, ASRock Super Computer X58 motherboard, ATI Radeon HD 4870, and Seagate 320GB SATA 2.0 hard drive.
The power supply ran on this system without any problems to speak of. The 140mm fan was also extremely quiet and we ran into no setup issues with the modular cables. Per our standard power supply testing procedures, we monitored the voltages when the system was idling within the GNOME desktop for 30 minutes and then the load testing was done by running the GraphicsMagick and Nexuiz tests from the Phoronix Test Suite. The voltages were monitored using a digital multimeter.
With dual +12V rails, modular cabling, a near silent 140mm fan, 80+ Certified, ATX12V V2.2 / EPS12V compatibility, SLI Certified, and OCZ branding, what would you expect this power supply to cost? $120? $160? This power supply is actually very inexpensive. The OCZ ModXStream Pro 600W will only set you back about $90 USD. This is actually an incredible bargain compared to the OCZ Fatal1ty power supply we looked at recently that cost $140 and many other power supplies that can easily approach $200 USD. The voltage rails were stable and in good standing, each of the +12V rails has 25 Amps, the power supply fan was quiet, and the modular cables worked out well. On top of all of that, this power supply is backed by OCZ with an excellent three-year warranty. About the only complaint we could come up with is that in some very large cases -- like the SilverStone Temjin TJ10 where the power supply is also bottom-mounted, some of the cables may not reach the top of the chassis. Beyond that we would recommend the OCZ ModXStream Pro 600W as a strong buy to anyone looking for an affordable ~600W power supply.