OCZ GameXStream 850W Review

OCZ recently made headlines when they acquired one of the top players in the power supply industry. The company was producing pretty good power supplies long before that happened though, and we will be taking a look at one of those units today.

Category: Power Supply
Manufacturer: OCZ Technology
Product: GameXStream 850W SLI
Gallery: Click Here
Price: $169.99

Power supplies today are huge. You can tell just by looking at them. If
you have access to an old pre-built PC from Dell or HP, open it up (the
warranty is void by now, no worries) and take a look at the power
supply. Compare that with the one powering your high-end gaming PC of
today, and you might be quite taken aback. Though some manufacturers
have managed to continue with true compliance to ATX size standards,
all too many have abandoned these dimensions and made the behemoth
power supplies we have seen cropping up over the past two years. While
the Thermaltake ToughPower 1200W PSU
we reviewed a couple of weeks ago was a huge power supply in its own
right, it paled in comparison to such products as Enermax’s Galaxy
1000W and a similar unit from PC Power & Cooling (OCZ Group). Power
supplies are not growing just in size either.

If
examining the maximum outputs of power supplies over the past two years
tells us anything, it is that power supply internals are increasing in
quality and size right along with their swelling exteriors. 350W was a
huge amount of power about 5 years ago. Today, you would be
hard-pressed to find any kind of high-end system (with the exception of
a Shuttle, perhaps) that could be well-supplied or let alone run on
350W. Today we see power supplies with up to six +12V rails providing
the juice for two honking video cards (soon to be three honking video cards),
quad core processors, and disgustingly huge hard disk arrays. 1200W is
not an uncommon number to come across when browsing the PSU inventories
of your favorite e-tailer these days. If certain power supplies occupy
a form a factor almost double the physical size of their ancestors,
then the inside components of each and every power supply claiming high
outputs must have doubled as well, right?

Not necessarily. Thanks to enhanced quality of PSU components like
MOSFETS, transformers, and capacitors, certain PSUs have managed to
reach pretty high output ratings from the same ATX form factor of old.
The 850W GameXStream power supply from OCZ Technology is one such
device, and we will be taking a look at it today.
{mospagebreak heading=Introduction&title=Features and Specifications}

Features & Specifications

Right off the bat you can tell this power supply is pretty small. Not
only is it actually shorter in the length dimension than the width, but
the fan is actually smaller than in some of the larger power supplies
we have seen in order to accommodate this. The 120mm LED fan on the
GameXStream 850W PSU (GXS850) is also the subject of two out of the
five main features touted on the front of the unit’s packaging: Silent
Operation and Superior Cooling. The fact that this fan is 120mm as
opposed to the generally more quiet and more powerful 130+mm fans we
see on some of the other high-powered units these days makes us
automatically skeptical of these two claims, so we will be paying close
attention to them during our testing.

In addition to the unit, the GXS850 box houses a standard power cable
to connect to the wall, a small booklet, and four case screws. This is
not a very impressive package at all. On the Thermaltake TP1200W unit
we reviewed previously, there were different accessories like 6 to
8-pin PCI-E adapters and a silicon riser (for reducing vibration). In
other power supply boxes, there are even more accessories, such as zip
ties for cable management. Having some of these extra luxury features
would have made a nice, and we can only assume very inexpensive,
addition to the GXS850 package.

The power supply itself is quite attractive in its simplicity. The
finish is a matte black, which gives it a sort of stealth-like
appearance, similar to what can be found on Christopher “Big Black”
Boykins’ 1979 Ford Pinto. We actually prefer this kind of finish on a
power supply because while it is not the most prominently displayed
item in the computer, being prone to fingerprints like some of the
excessively glossy units we have tested in the past can never be
considered a good thing - unless of course you have a thing
for fingerprints. In the back of the power supply is the power cord and
a small rocker switch. You might also notice the lack of a VAC switch,
meaning that this power supply can automatically adjust depending on
what type of circuitry you have in your house (which depends on where
you live in the world).

Finally
on the right side of the power supply are the stickers that display the
output ratings and quality control passes. One interesting note about
the output label is that the one on the power supply itself is not the
same as the one posted on OCZ’s website. This would not be a problem if
it looked a little different or something, but the two sources offer up
quite different specifications; something that could be very confusing
for potential consumers. Luckily the specs listed on the actual label
are superior to those on the website, so anyone who buys this unit
based on the website information should be pleasantly surprised.

{mospagebreak title=Features (cont)}

Moving inside the unit, we are greeted with a pretty good sign. OCZ’s
original equipment manufacturer for this power supply appears to be FSP
Group (the “SPI” displayed on the transformer is the abbreviation of
Sparkle Power, Inc., a company supplied by the Taiwanese FSP Group). In
addition to this dead giveaway, the PCB is the standard FSP cream color
that is found on most all power supplies manufactured by FSP, including
those from OCZ, Sparkle, Mushkin, and Zalman. Taking a quick look at
the fan reveals that it is actually manufactured by Protechnic
Electric, one of two companies FSP uses for fans in their power
supplies (the other is Yate Loon Electronics). The reason all of this
is a good thing for OCZ is that FSP Group has an outstanding tradition
of providing excellent parts to their customers. Their commercial
channel branch, Fortron Source, has earned a great reputation on
enthusiast review sites and consumer review sites like Newegg.com for
high marks in stability and quality.

Taking a look at the PCB configuration, you can see that OCZ chose a
single capacitor design for this power supply, which is typical for
units in this output range. You can also see on the left side of the
PCB (the side farther away from the connector cables) that there is
indeed active PFC on the unit. All of these things are pretty typical
of power supplies these days, but there are two things that have yet to
be discussed that make this unit a bit different from any of the others
we have reviewed in this range. The single large transformer is a
departure from what we have seen in every other ultra high output power
supplies in the past. Though we do not have any documentation to prove
it, we believe this single transformer is responsible for all four +12V
rails and the +5V rail (and subsequently the +3.3V rail). There is a
smaller transformer that likely produces the -12V and +5Vsb rails. Our
reasoning for this comes from looking at the output label, which
suggests that the 6 rails mentioned are grouped together in one
category, while the other 2 are separate. Whatever the case, the bigger
story here is that unlike every other power supply we have reviewed,
the heatsinks in the GXS850 are relatively tiny and do not dominate the
interior of the unit. We have no idea why this is, though it can
probably attributed to more efficient, higher quality MOSFETS and
transformers.

On
the surface, the lack of heatsink area does not bode well for the
“Superior Cooling” claim on the box. However, it could be that the
smaller heatsinks allow for more air to get to the crucial components,
due to the lack of obstruction. This could also prove beneficial for
the “Silent Operation” claim, as less turbulence in the fan’s output area potential spells silence.

The last thing to note about this power supply before diving into
testing concerns the included connectors. There are six SATA
connectors, six standard MOLEX peripheral connectors, two auxiliary
power connectors, one 20+4-pin ATX motherboard connector, one 4 or
8-pin EPS12V CPU connector, and two PCI-E connectors. It says on the
OCZ website that this power supply is certified for NVIDIA SLI
technology. It states on the product box that this power supply is
“Multi-GPU Ready”. However, there are only two PCI-E connectors
incorporated into the product. Sure you can run two not-top-of-the-line
video cards in SLI or CrossFire with the included connectors, but it
seems to us that people that are looking for a unit in the 800+ Watt
range are probably thinking dual 8800GTX, 8800Ultra, or HD 2900XT
setups.
{mospagebreak title=Testbed and Methods}

Testbed and Methods
Test Setup

Case: Thermaltake Armor
Power Supply: Tagan Turbojet TG1100-U96 1100W | Thermaltake Toughpower W0133 1200W
Motherboard: ASUS L1N64-SLI WS
Processor: (2x) AMD Athlon 64 FX-74 (Quad FX)
Hard Drive: (2x) Western Digital WD1500ADFD 10,000RPM, RAID-0
Hard Drive: (1x) Western Digital WD5000KS 7,200RPM
Video: (1x) NVIDIA GeForce 8800GTX
Memory: 4096MB (2x(2×1024MB)) Corsair XMS2 PC2 6400
Optical Drive: Lite-ON SHW160P6S05
Cooling: (2x) Vigor Monsoon II

Software Configuration

Motherboard BIOS: L1N64-SLI WS Release BIOS 0124
Operating System: Windows XP Professional with Service Pack 2
Video Driver: NVIDIA ForceWare Version 158.22 (May 17 release)

We were pretty pumped going into this review because it would be the
first time we were testing a power supply technically unable to handle
the load produced by our new test system. However, when we got the unit
in our hands and it only had two PCI-E connectors we got pretty bummed
out. We could have used a couple of those “two MOLEX to one PCI-E
conectors”, but we did not have any on hand so that was not a
possibility at the time. Instead, we opted to remove one 8800GTX from
our normal test system. Not only would this remove the need for four
PCI-E connectors, it would also bring the total maximum power
consumption of the system down within capacity of the GXS850. Since we
do not yet have the resources to acquire the equipment necessary for
testing all the aspects of a power supply we would like to, we are
forced to settle with this for now.

As usual, we will be recording the voltages across each measurable rail
with a digital multimeter at four distinct loading conditions.

System Startup: Immediately prior to the Windows scroll bar appearing.
Idle: After Windows has started and background tasks have been loaded into memory.
Normal load: 50% processor load via two instances of Prime 95.
Full Load: Four instances of Prime 95 and a single instance of
3DMark06. Measurements here are taken during the “Canyon Flight” test,
as the big scary fish thing pokes its head out of the water for the
second time.

{mospagebreak title=Test Results}

Tagan Turbojet TG1100-U96 1100W

We tested the Tagan Turbojet TG1100-U96 once before in our review of
the Thermaltake TP1200W. The one being tested today is actually not the
same as the one used in that review. The reason for this is that in the
interim the previous unit died out. This is a shame considering it was
fairly new at the time of that test. While we are certainly not making
this accusation and will not do so until we have a chance to fully test
the unit, it seems as though the line might suffer from reliability
issues. Regardless, as it was the incumbent power supply in our test
system, we ended up testing it first. Please keep in mind that the
numbers you see here are very likely different from those that can be
found in our previous review for two reasons: this is not the same
exact unit and the total load being placed on the unit is considerably
less in this review.

Here
we see great numbers across the board from the Tagan PSU. While some of
the numbers are a little bit higher than the optimal target, there is
very little fluctuation on the rails. This performance is a bit better
than what we have previously seen from this model, probably because the
load being placed on it is not nearly as high. Before we move on to the
OCZ unit, it should be noted that these two power supplies are not
really competitors. The TG1100-U96 from Tagan is in what we would like
to call the “disgustingly-high output” range, while the GXS850 from OCZ
is just in the high output range.

OCZ GameXStream 850W

We did not have high hopes for the performance of this power supply
going into the test. After all, it has only one transformer for 4 +12V
rails, relatively miniscule heatsinks, and is much smaller than its
competition. Don’t get us wrong, we had confidence that the unit was
going to perform fairly well by the shear virtue that it is really an
FSP Group product, and those have garnered quite a nice reputation for
being serious performers. We were also very interested to see how noisy
(or quiet for that matter) the power supply was while operating.

The results here are not too surprising. It is clear that there is a
large amount of fluctuation across the rails under different loading
scenarios, and that the numbers themselves are a bit higher than the
optimal target values. While the fluctuation recorded is far more
dramatic than in any other power supply we tested, at no point did the
voltages spike above or below the accepted values. The magnitude of the
fluctuation itself is also far from what is considered problematic.
This is all pretty much expected from a unit that taps most of its 850W
from a single transformer. You can see how the +12V rails are affected
by this when the system is subjected to maximum load.

{mospagebreak title=Final Thoughts and Conclusions}

Final Thoughts and Conclusions
In terms of quietness and coolness, two features heavily touted on the
GXS850 package, the power supply is pretty impressive. Not once did the
noise level exceed the ambient conditions produced by the cooling
solutions used in the system. The single 120mm that had us worried at
the start of the review proved to be quite capable of moving enough air
quietly, as the power supply did not hiccup at any point during the
review. It should also be noted that there is an INSANE amount of air
flying out the back of the unit while the fan is running. The quantity
of air here seems to be far more than on any other power supply we have
tested. This may be the result of a more direct airflow out the back of
the unit thanks to smaller heatsinks, but it was very impressive
nonetheless.

While the performance of the power supply is a little bit lower than
what we have seen in the past, it is not what we would consider bad by
any stretch of the imagination. The performance is in fact right in
line with what we would expect from the single transformer design of
the unit. If this power supply can perform well without costing an arm
and a leg, the numbers we have seen today should not be a detriment to
the overall value of the unit. On the topic of price, this unit comes
in at $169.99 according to the GotFrag pricing engine. This is $27 less than the $196.99 price tag of the Real Power Pro 850 from Cooler Master
that we reviewed a while back. In our opinion the increased performance
of the RPP850 is not worth the $27 extra you would be shelling out for
the unit. However, one feature present in the RPP850 that is lacking in
the GXS850, the four PCI-E connectors, definitely makes it worth the
extra money.

In the end, the GXS850 performs well for the price and is backed by a
generous three year warranty. The OEM used for the GXS850, FSP Group,
is another thing that makes the GXS850 a good product. However, the
lack of certain features and the slightly inferior performance prevent
the GXS850 from being a truly standout product in the high output power
supply market.

Pros
+ Small form factor will fit in micro ATX cases without a problem
+ High quality components; only small heatsinks needed
+ Attractive design
+ Abundant peripheral connectors
+ Great cooling fan
+ Active PFC
+ Cheaper than competitors
Cons
- Only 2 PCI-E connectors
- Unimpressive package
- Spec discrepancy with website
- Performance not quite as good as competitors
- Advertised performance rated from 20C, unrealistic for ambient system temperature
Rating
7.4 out of 10