OCZ 780W ModXStream Power Supply Review

There's an 800 pound gorilla in the room, so let's deal with that before moving on. The tech world's in a buzz over OCZ's recent buyout of PSU giant PC Power & Cooling, and the questions on everyone's mind are, how will this affect their business model, and who gets to keep their name? In short, the two companies will continue to co-exist with separately branded lines, and according to an interview conducted by XBitLabs, OCZ's Executive VP & CMO Alex Mei says, "the OCZ PSU’s will target mainstream, gamers, modders, entry enthusiasts, and system builders. The PC Power & Cooling solutions are ideal for upgrading Dell systems, enthusiasts, servers, commercial, and mission critical applications."

Today we're looking at OCZ's update to their modular line, the ModXStream 780W (also available in 900W flavoring). While certainly not new to the modular world, the original ModStreams topped out at 520W and just 28A on the +12V rail, making the XStream version a beast by comparison. And just in time too, as cutting edge videocards continue to demand increased juice, while multicore processors trickle into the mainstream. Can the ModXStream walk away unscathed and a modular marvel as we throw everything we've got at it, or are we in for some modular mayhem? We aim to find out!

Features

EZMod Advanced Cable Management System
Active PFC
120mm LED Fan w/ PowerWhisper Technology
EMI Isolated Casing
Multi-GPU Reader
Quad +12V Rails

DC Output:	+3.3V	+5V	+12V1	+12V2	+12V3	+12V4	-12V	+5Vsb
Max Output Current:	30A	30A	20A	20A	20A	20A	1A	3.0A
Max Combined Power:	175W						25W
Max Combined Power:	755W						25W
Total Power:	780W

CONTENTS AND CASING

As the backbone of your swank dream machine, the power supply qualifies as arguably the most important component in your rig. And when choosing a PSU, many factors come into play, the bundle just isn't one of them. Our ModXStream came with a user's guide, power cord, baggie of screws, and of course the modular cabling.

The ModXStream's EMI isolated black casing remains unchanged from their GameXStream line, and we couldn't be less concerned with a power supply's aesthetics, as they're hidden by nearly every case on the market (including those with a side window). Though we will admit to being absolutely infatuated with the reflective mirror finish found on some other lineups in OCZ's stable, such as the ProXStream. Vain, you say? Guilty!

The ModXStream measures150mm long (that's 6.5" for those raised in a US public school), and should have no trouble fitting in any ATX chassis on the market.

Turning the unit to the side and looking at the label cuts through the fluff and gets us to the nitty-gritty. We see that the ModXStream comes with four +12V rails, and whether you prescribe to the single or multiple rail philosophy, it all takes a back seat compared to the total amperage available. Today's systems feed heavily off of the +12V line(s), and generic PSU manufacturers are notorious for skimping in this department and feeding the amps elsewhere, thus still allowing them to claim a high wattage rating on the box. We say 'boo' to them and 'hooray' to companies like OCZ that give us adequate +12V amperage to work with.

The ModXStream ships with four +12V rails, each capable of supplying up to 20A at any given time. For those of you doing the math at home, put the pencil down for a moment. This does not mean we're given a total of 80A to work with, as a common misconception is to simply add all the rails together. We need to look at the wattage distribution, and we can see that 755W gets supplied to the +3.3V, +5V, and +12V lines. Since we paid attention to our electrical engineering notes, we know that Watts = Volts * Amps. Plugging our numbers into that formula, we divide 755W by 12V, which gives us a theoretical maximum 63A on the +12V line, minus whatever juice the +3.3 and +5V rails consume.

Interestingly enough, OCZ's downloadable Product Specification sheet breaks down the wattage distribution slightly different than our test sample's label:

Instead of 755W, the above PDF shows 720W being available, resulting in a theoretical maximum 60A (they even do the math for us, but for the sake of practice, 720W / 12V = 60A). Either way you slice it, the ModXStream provides plenty of amperage across the +12V rail(s) to feed a power hungry rig, and we'd be surprised if our dual-GPU, quad-core testbed manages to cause a hiccup. We'll find out in just a bit...

Peeking at the back, we see the standard honeycomb grill, a common trait among most power supplies. With the 120mm fan keeping the components cool, the grill provides an effective exhaust for hot air to be whisked out of the unit, and out of your chassis.

COOLING AND CABLING

Most power supplies have moved to 120mm fans on the bottom of the casing, and the ModXStream is no exception. These large fans cover just about the entire surface, ensuring that the internal components all receive adequate airflow.

Like the GameXStream line, OCZ chose to stick with a Pyrotechnic Electric dual ball bearing fan, model number MGA12012HB-O25. A good choice too, as the 2500RPM fan remained quiet during testing while providing adequate airflow. And of course it glowed blue throughout testing too (would it be an OCZ product otherwise?).

The main ATX 20+4 pin, supplementary 4+4 pin, and 6 pin PCI-E1 cables come attached to the ModXStream, with all other cabling of the modular variety. We were a bit surprised at the absence of labels above the modular connections (they appear on the box's pic), and if you're the type that has ever successfully pushed a square peg into a circle hole, well, labels probably wouldn't have helped anyway.

The ModXStream comes with a bevy of cables, giving you enough connections to deck out your rig and, if desired, totally negate the main reason for buying a modular power supply in the first place. In total, the ModXStream packs the following:

20+4 pin ATX	x1 (attached)
4+4 pin EPS12V	x1 (attached)
6-pin PCI-E	x1 (attached)
SATA cables, 3 Connectors Each	x2 (modular)
Peripheral 4-pin Cable (2 + 1 FDD Connector)	x2 (modular)
2 (4-pin) CPU Auxiliary Connector	x1 (modular)

All cabling comes sleeved in a black mesh, including the area in between connectors. We've seen many power supplies leave this area naked from sleeving, and we really have to applaud OCZ for the extra effort. After all, one of the major aspects of owning a modular power supply is maintaining a tidy interior, a difficult feat when dealing with the eyesores of exposed wiring.

INTERNAL AND TESTING

Let us preface our internal examination with the same warning we apply to all of our power supply reviews. Opening up a PSU not only voids your warranty, but also presents a serious health risk. Even after turning off and unplugging a unit, there can be enough charge stored to significantly shock and/or cause a fatal injury to anyone poking around inside. In short, let us at HardwareLogic be the ones to stand in a bucket of water while snapping shots of the internal componentry, and keep the cover on at home.

Here's a test you can do at home. See that generic 600W unit you have sitting in the corner that sold for $25? Pick it up. We're willing to bet it's a featherweight unit, which, if you frequent LAN parties, is a good thing, right? Wrong. As a preliminary qualifier, the weight of a power supply generally dictates which class it's likely to fall into. Generic units cut costs by skimping on internal components, which vary from regulating clean power to thermal management (large heatsinks), and the result is a less reliable, albeit lighter power supply..

Picking up the ModXStream, it was quickly apparent which class it belonged to, and opening up the unit revealed no surprises. Inside the heavy power supply sit a series of heatsinks, capacitors (CapXon and Teapo, for those that pay attention to that sort of thing), coils, and more.

Many power supply companies outsource their production, giving the manufacturer a set of specifications to follow. This is not a bad thing, so long as the outsourced company puts together a good product. Peering closer to the PCB reveals the ModXStream to be a Fortron unit, the same company that produces the GameXStream series, and one that has a solid reputation for churning out quality power supplies. With the PC Power & Cooling acquisition, it will be interesting to see if OCZ sticks with Fortron for future models, or begins outsourcing to Seasonic, another solid company that's also responsible for PCP&P's Silencer line.

Testing Methodology

Here at HardwareLogic, we strive to provide our readers with accurate and real-world results of every component we put through the wringer. This philosophy presents a challenge when testing power supplies of increasing size, as it would take one monster of a test bed to flex the capabilities of these big watt behemoths. We're simply not content to hook up a high end system, record the voltages, and call it a day. For this reason, we're in the process of obtaining professional level equipment to better stress and test a power supply's capabilities, and hope to have the new system in place by the end of summer. In the meantime, we'll be conducting our power supply reviews in the most real world way possible, despite the limitations of such testing. This means outfitting a high end system with dual videocards, increasing the voltages, and overclocking our processor to simulate the computing habits of enthusiasts. Our testbed today consists of the following components:

Processor	Intel Core 2 Extreme QX6800 Quad Core
Motherboard	ECS PN2 SLI2+ Extreme 680i
RAM	2GB Corsair DDR2-1066
Videocard(s)	EVGA 8800GTS and Foxconn 8800GTS (SLI)
Hard Drive(s)	2 x Western Digital 400GB/16MB
Other Components	2 x DVD Opticals, Creative X-Fi Fatal1ty, Mouse, Keyboard

Test Results

Our testing today focuses on measuring the +12V, +5V, and +3.3V rails both at idle and with a full system load. We then take a second set of measurements after overclocking our processor's four cores to 3.47GHz (up from 2.93GHz at stock), while also increasing both the CPU vCore and RAM voltage.

The ATX specification allows a 5% variance in either direction, so we'll be looking to make sure our unit is not in danger of running out of spec. Equally important, if not more so, is whether or not these rails remain stable or have a tendency to jump around. In other words, do they provide clean power? We'd much rather have a power supply whose +12V rail remains at a constant 11.90V (well within the 5% variance allowed) over one that measures +12V on the nose but repeatedly fluctuates all over the place.

	Stock Idle	Stock Load	OC'd Idle	OC'd Load
+12V1 (CPU)	12.60	12.52	12.60	12.53
+12V2 (PCI-E2)	12.62	12.56	12.61	12.54
+12V3 (Mobo Accessories)	12.62	12.54	12.61	12.55
+12V4 (PCI-E1)	12.62	12.53	12.61	12.56
+5V	4.98	4.99	4.98	5.01
+3.3V	3.30	3.30	3.30	3.29

Both the +3.3V and +5V rails registered an almost perfect reading, and refused to budge during testing, including our overclocked settings. It's not until we examine the +12V rail(s) that we become slightly apprehensive. All four +12V rails measured high right from the start, a trend we're noticing more and more among power supply manufacturers. One possible reason for this could be to compensate for high end systems, as well as future upgrades. Dual-core processors have become the norm, with quad-core computing not far behind. And much to our chagrin, videocards continue to increase their power demands.

Whatever the reason, we're a bit uncomfortable seeing the ModXStream's +12V rail(s) measure around the 12.6V mark, the 5% cutoff point according to the ATX specification. We'd feel better about it if our testbed was a mid range system, but we're running the fastest quad-core processor currently on the market (QX6800), along with a pair of mid-range videocards (8800GTS). To quell our curiosity on how it would handle a more budget oriented rig, we hooked up the ModXStream to a system outfitted with a 3800+ X2 processor and 7600GS videocard. Our impromptu reading registered 12.64V, giving us some solace at not seeing the voltage spike way up.

When it came time to overclock, the ModXStream gave nary a flinch, with the voltages remaining virtually unchanged. Running a load didn't seem to matter much either, and just like the GameXStream that uses the same 120mm fan for cooling, our test unit remained very quiet.

Segment	Score	Comments
Feature-set	9/10	Modular cables Full sheathing, including between connectors Active PFC and high efficiency
Cables and Connections	16/20	Six SATA connectors enough for a high end machine Four molex connectors will be sufficient for most setups, but we'd liked to have seen a couple more thrown in Will need molex-to-PCI-E adapters (not included) if running two 8800GTX cards No 6+2 pin PCI-E connector for newer videocards
Power	19/20	780W with 60A available on the +12V rail(s) will accommodate all but the most power hungry rigs No official SLI certification, though our testing showed it's capable
Performance	15/20	Neither an overclock or load could make the ModXStream flinch Unit remained stable throughout testing +12V rail(s) measured high, breaching the 5% ATX specification +12V rail(s) were a bit jumpy under load, though this is more of a nitpick than a concern
Noise and Cooling	10/10	Ran quiet and stayed cool...nuff said!
Warranty and Support	9/10	Three year warranty, though we've seen five year and even lifetime guarantees start to enter the marketplace Backed by OCZ's PowerSwap replacement program, which means they'll replace a defective unit with a brand new PSU, and not a reconditioned one OCZ's reps are some of the best we've worked with, and can often be found participating in community forums (psst, OCZ reps, we have a forum too!...) Extensive Support Page contains warranty information, contact information, online RMA tracking, support forums, and more
Price / Value	8/10	Competitively priced with other modular units in its class at Newegg

Our Recommendation

What used to be slim pickings in the not too distant past, the field of quality modular power supplies has become a crowded market, and today OCZ joins the fray. We couldn't say that about the original ModStreams, a line that topped out at only 520W and a mere 28A across the single +12V rail, leaving power users wanting. Not one to watch other companies lead the charge, OCZ's ModXStream puts them back into the modular game with a PSU line more than capable of handling today's demanding systems.

Lest we dote all over the ModXStream, there are some flaws that temper our affection. Despite the recent propensity from PSU manufacturers to beef up the voltage on the +12V rail(s), we're a bit concerned that the ModXStream hovers around 12.6V on a high end system, the cutoff point according to the 5% tolerance allowed by the ATX specification. This didn't seem to affect stability, but if we had our druthers, we'd like to see that voltage toned down a notch. And while we're making wishes, we'd ask the manufacturing genie to throw in a couple more molex connectors, PCI-E adapters for GTX videocards, and a couple of 6+2 pin PCI-E connectors for newer GPUs. And if such a genie really does exist, we'd also wish for a pet monkey trained in kung-fu. Seriously, how awesome would that be??

Getting back to the power supply (heh, kung-fu monkey...where do we come up with this stuff?), we feel confident in the ModXStream's ability to power an enthusiast level rig, whether you're running dual videocards, overclocking, or both. And when it comes to attention to detail, we love that OCZ went the extra mile to sheath the cables in between connectors, an area we've seen too many other manufactures skimp. Pricing is on par with other offerings in it's class, but as we've said before, OCZ's customer support remains a cut above the competition. At the end of the day, the ModXStream puts OCZ back into the modular saddle with plenty of power to ride off into the silicon sunset.

Other Reviews of Note

It's always nice to have more than one opinion on a component before you spend your hard earned money. For one, we may see something others missed, or vice versa. As with all reviews published at HardwareLogic, we'll not only give you our recommendation, but also point out reviews from some other great sites from around the web.
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