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- Date:
- Thursday , October 16, 2008
- Author:
- Paul Johnson
- Editor:
- Kyle Bennett
- Google +1
Xigmatek NRP-MC851 850w Power Supply
No Rules Power! That makes for a good product tag line, but we all know damn well that power without rules makes for a terrible computer power supply. Does Xigmatek's NRP 850 watt PSU play inside the rules when it comes to serving up 850 watt?
Overview
The first thing we are going to look at with the Xigmatek NRP-MC851 is its packaging, accessories, and documentation. While normally none of these items is a real make or break item for a power supply the packaging quite often contains a lot of information about the product we are purchasing. The inclusion of an owner’s manual that provides actual information about our product is also of great help. Accessories are almost unnecessary with a power supply as the unit is self contained, unless it is modular, but there cases where a manufacturer can include useful accessories to make installation, routing and use more efficient.
The packaging for the Xigmatek NRP-MC851 hearkens back to a time when jean jackets were all the rage as the sleeve containing the packaging looks like something designed by Levi Strauss. Unfortunately, while very retro stylish (you aren't going to see many packages like this on the shelves of Fry's or Microcenter), the packaging only includes some marketing points, pictures of connectors, and some certification stamps for electrical compliance. However, going off of the marketing from the webpage we know that the unit is advertised as being 80Plus approved, SLI approved, and carries a 3 year warranty. (Warranty information is not on the webpage). After checking the SLIZone website we find that the unit is indeed rated for 7900GTX SLI, but given what we find below this seems to be a very conservative rating if the paper numbers are to be believed. The unit is also 80PLus listed, but just for Climate Savers 1 which is 80%-80%-80% at 20%-50%-100% loads. Lastly, the NRP-MC 851 carries a three year warranty according to the included warranty card (this information was not available on the Xigmatek contact page and at the time of writing there was not distinct support page available). Now while three years is certainly better than the warranty some units carry, it is still on the short end of the spectrum when it comes to high end power supplies. Given that this unit’s warranty documentation is sketchy at best on support, and the warranty card indicates that the warranty is ONLY valid with a completed warranty card, users should be very careful in their record keeping as these are not the most liberal (or well documented) of warranty policies going in the enthusiast power supply market at this time.
The connector count and the power allocation for the Xigmatek NRP-MC851 falls right in line with what we would expect from the CWT PSH line of power supplies. The unit has a very good total of 62A or ~87.5% of its capacity available on the 12v rails for powering modern systems that are 12v oriented and this is all fairly standard. Now, how that 12v capacity is broken down is a bit more interesting than its capacity. Typically, a power supply with more than 1 12v rail will have the yellow (12v) leads color coded to identify which lead goes to which rail and the NRP-MC851 did have this done. However, the color coding does not match the breakdown identified in the manual, or what was provided by Xigmatek. When everything was said and down though, the breakdown listed in the manual is the most correct (albeit with an incorrect number of connectors labeled) and is identified above as Rail Breakdown in Manual. As such, the four PCI-Express connectors on this unit have 60A available to them which should be sufficient to run just about any SLI or CrossFire configuration that can be configured with four PCI-Express connectors. Further, the 18A available to 12v1 and 12v2 should be sufficient for powering the devices fed by these as well. The unit can natively support a total of 13 SATA/Molex devices. Lastly, it should be noted that this unit is advertised as having ripple/noise values of up to 240mV on the 12v rails, which is double the ATX12v specification limit. In our previous testing of CWT PSH based units the 12v rails have been noisy, typically peaking close to 90-100mV, however to date these units have not been over 120mV when run inside of their originally designed DC output capacity. As such, I doubt these advertised values will come to fruition in our testing, but advertising values above the ATX12v specification limit is certainly not a good thing or a promising start.
Once we open the NRP-MC851 box that is housed in an interesting 3/4 sleeve packaging we find the power supply itself, the cables, the manual, a warranty card, a bag, a pouch for the cables, some silica, and a baggy of screws. As we have seen from a number of companies now that use the CWT PSH platform the manual that comes with the NRP-MC851 is mostly complete. The manual weighs in at a book like length of 61 pages (in only 5 languages) and includes all the technical specs including ripple/noise (they even tell you how to properly measure the ripple/noise), voltage regulation, pinouts for connectors, over voltage set points, 12v rail distribution, and on. The manual with this unit is very informative but does lack the warranty information, and the rail distribution is slightly off in the number of connectors configured with this unit.