Four of these SATA to 4-pin Molex adapters are included as part of the bundle (hence why there are so many SATA connectors). I really wasn't impressed with their quality. Looking at the SATA end, it just looks and feels cheap. Fitting the adapters on the SATA connector was hit or miss; two of them slid into place without a fight, while the other two had me struggling to get things right. Six 4-pin Molex connectors are present on the 850 Precise... more than plenty for my needs so I did not have to use these adapters.
Before installing the 850, I first connected it to my CoolMax Power Supply Tester. This will tell us a few things. First, we will know up front if the power supply is fully functional or defective. Few things can irritate you more (and give you a scare) than installing a new power supply only to find it is defective. Also, the power supply tester will let us see if all of our voltage levels are within spec.
The power supply tester is very easy to use. Simply make the necessary connections to the testing unit (4-pin Molex, ATX power connector, 4-pin Floppy style connector, 6-pin PCI-E connector and a 4-pin or 8-pin connector), then plug the power supply into an electrical outlet, flip the power switch (if applicable) and the tester will come to life (granted, the power supply isn't dead). Everything looks to be within spec, so let's move ahead with testing.
I will be testing the 850 Precise on my dedicated test system, which consists of the hardware listed below:
Intel Core 2 Duo E6600 @ 3.5 GHz
Ultra ChillTec CPU Cooler
EVGA 680i SLI Motherboard
Two 8800 GTX cards in SLI configuration
2 Gb Corsair XMS PC2-6400 Memory
74 Gb Western Digital Raptor 10k RPM HDD
HighSpeedPC Top Deck Tech Station
Lite-On Optical Drive
I used a digital multimeter to obtain voltage readings. Since most power supplies correct any fluctuation in the current to the rails before our multimeters would even notice, we're unable to monitor every output in real-time simultaneously. To record idle voltages, I simply let the system sit idle in Windows for 20 minutes. For load voltages, I ran Prime 95 (one instance per core), Winamp, AIM, multiple FireFox windows and defragmented the hard drive, all while playing Need for Speed: Carbon on max graphics settings. This combination of programs put a nice load on the system.
As the voltage results confirm, the 850 Precise had no problems powering my highly overclocked 8800GTX SLI test system. There was a slight bit of voltage fluctuation at the PCI-E connectors but this is normal and is nothing to be concerned about. The 5v and 3.3v rails held rock steady throughout testing.
The 850 performed well in testing and equally as well in other categories. As for pure aesthetics, NZXT has hit a home run. The gun metal (black chrome) mirror-like finish is superb, and the 120mm thermal controlled blue LED fan offers a nice contrasting glow. The fan was very quiet throughout testing, a good bit more than some of the 1KW systems I have tested recently. I also liked the modular cable system. Although it is proven that some power may be lost with a modular system, I think the effects are minimal and a fair trade-off for eliminating the clutter of cables that go unused in a system. This also promotes better airflow throughout the system. NZXT fully sleeved all of the cables in black mesh, with the exception of the 6-pin PCI-E cables which appear to be shielded and are covered with a clear plastic coating. There are plenty of connectors (especially SATA connectors) to power all of your hardware and hard drive(s). The "continuous" / "split" 12v rail switch is something new for me. Personally, I would be just fine if NZXT didn't include this option and went with a single 12v rail. The added zip ties and Velcro straps only help with tidying up your system after installation and make a nice, well rounded bundle.
The one thing I would like to see NZXT improve upon are the SATA to 4-pin Molex adapters. These adapters simply felt cheap and connecting them to a SATA cable seemed hit or miss. Higher quality adapters are certainly in order.
The NZXT Precise 850w packs a strong punch at a very attractive price point. With just 150w less than the 1KW "monsters" now available, the difference in price is about $120. As of writing, the Precise 850w sells for just under $230 at a popular online reseller.
OCIA.net has awarded the NZXT Precise 850w Power Supply our seal of approval.