FSP Booster X3 300w 12v PSU Page: 1

So you've just upgraded your PC with 2 brand-spanking-new high end graphics cards which you plan to run in SLI / Crossfire. You set it all up, turn it on, only to find that your faithful 480w power supply which has been serving you well for the past year, just cant meet the demands of these power hungry cards.

Up until recently there has only been one option: buy a new power supply. This can be pricey, with most decent SLI certified units starting at around £80-100. However FSP have come up with a more affordable solution, which will not only solve your SLI power woes, but also ensure your PC has enough power for future expandability.

Enter the Booster X3 300w VGA (+12v) power supply. Designed to fit in a spare 5.25" bay, and powered directly from the mains, the Booster X3 provides a total of 25a on a single 12v rail, which should keep your dual card setup happy.


Taking a step away from the highly flashy packaging we saw on FSP's Epsilon series of PSU's that I reviewed last week, FSP have opted for more professional look. Yet again, it is a shame that most of us people based in the UK won't get to see it out on retailers shelves, but will instead need to purchase it over the internet.

Booster X3 Packaging Booster X3 Packaging

Booster X3 Packaging Booster X3 Packaging

The front and sides of box give some basic information about the unit, including its power output and cooling capabilities. Also shown on the front of the box is a picture of the unit with its glowing blue fascia sporting the FSP logo.

The back of the box goes into detail about how the unit works, and provides step-by-step instructions on how to install it. I find this a particularly great idea, as many people may be wary of purchasing such an inventive piece of hardware without knowing the steps required to install it.

As you can see from above, the BoosterX3 is very well protected from any kind of transportation damage by being totally encased in a styrofoam cut-out.

Booster X3 Components Booster X3 Screws

Included in the package are the following items:

- FSP Booster X3 300w unit
- Colour manual
- Power cable
- PCI Bracket for routing AC power inside case.
- Dual PCI-E cable
- Large bag of thumbscrews
- Cable ties

The Booster X3 comes with everything required to get the unit up and running. Strangely it also comes with a huge pack of thumb screws, which is a nice touch but in most circumstances won't be required as 4x cd-rom drive screws are all that's needed to secure the unit.

FSP Booster X3 300w 12v PSU Page: 2

The following information has been taken directly from FSP Group press release documents:

"Delivering a reliable, sustained power output of 300W (360W max) the FSP Group Booster X3 is perfect for semi-pro and pro gamers who demand the ultimate in super-stable 3D graphics acceleration" said Ann Kuo, Product Marketing Manager of FSP Group's UK Marketing Division.

FSP Booster X3 features FSP Groups' exclusive Auto-Power Recovery System (APRS), which working in conjunction with a systems existing PSU, enables the FSP Booster X3 to fully support installations of multiple, high and extreme performance 3D graphics accelerators such as ATI Technologies' CrossFire, NVIDIA SLI and future S3 MultiChrome.

Featuring a subtle blue LED illuminated front-panel and high-quality dual-intake cooling fans, the FSP Booster X3 is compatible with most well ventilated ATX personal computers with a spare 5¼" drive bay.

Easily installed in minutes, the FSP Booster X3 is both economical and quiet in operation (even under full load) and is crucially ROHS compliant.


- Active PFC (99%)
- Blue LED Front Panel
- Independent Power Source
- Dual Front In-Take Fan
- Auto-Power-Recovery System (APRS)


With 25 amps on the 12v rail, this unit should be able to power any current high-end SLI or Crossfire setup with ease and will hopefully be future-proof for a few generations of graphics cards to come.

FSP Booster X3 300w 12v PSU Page: 3
Appearance & Connectors

As previously mentioned, the Booster X3 unit fits in a 5.25" drive bay and shares the same dimensions as many CD/DVD drives.

As a result of this, FPS have not paid any attention to making the top/sides of the unit aesthetically appealing as they will not be seen. Instead they have focused all of their efforts on the front of the unit which has a blue illuminated dome etched with the FSP logo.

Booster X3 Unit Booster X3 Unit

Booster X3 Unit Booster X3 Unit

The front of the unit is made from black plastic and has grills that allow the fans mounted inside the unit to blow hot air out of the front of the case. It is also worth noting that the clear plastic dome on the front of the unit can be removed if it proves to get in the way of the drive bay door found on many modern PC cases.

The back of the unit has 3 plugs which all need to be connected in order for the unit to work. Starting from the left, we have the dual PCI-E connector, the molex connector (used to sense when the pc is turned on) and the main AC power plug.
Just above the plugs is a large grill, which allows the fans to draw air from inside the case over the PSU components.

Booster X3 Inside Booster X3 Inside

Booster X3 Fans Booster X3 Fans

The insides of the Booster X3 are well laid out, with plenty of room for the fans to pull air over the components. Aluminium heatsinks have also been used on the hottest components and have fins for better heat dissipation.

I was unable to find any adjustable potentiometers inside the unit, but after seeing the voltage output from other FSP units I'm hoping these won't be necessary.

The installed fans are manufactured by Protechnic Electric and are their 40mm MGA4012ZR models. Unfortunately I was unable to find any specs for these fans online.

Booster X3 Cables Booster X3 Cables

As the Booster X3 requires mains voltage, FSP have included a PCI Bracket, which allows for mains power to be routed inside your case.

I was slightly disappointed to see that the PCI-E connectors could not be plugged in indepentently. Instead you are required to have both PCI-E connectors in at all times. This shouldn't pose a problem for most people using the Booster X3 as they will be running an SLI/Crossfire setup, but it would have been nice to have two separate cables never less.

FSP Booster X3 300w 12v PSU Page: 4
Load Testing

In order for the results from all current and future PSU reviews to remain fair and comparable, Overclock3D uses a custom built Power Supply load stress tester.

The tester is capable of placing loads on the following rails:


+3.3v - 20a Load
+5.0v - 20a Load
+12v1 - 10a Load
+12v2 - 10a Load
+12v3 - 10a Load
+12v4 - 10a Load
(or 10-40a on a single +12v rail)

The results are collected from a Mastech MAS-345 Multimeter which logs its readings via RS232 to a PC.

Today i will be testing the FSP Booster X3 at 80% load (20 amps), which is as close to the maximum rated output of 25 amps as the tester can get before it trips the power supplies over-load protection.

Booster X3 12v Rail

At 80% load the +12v rail in the Booster X3 moved only by 0.05v, which is an amazing result, considering most high-end power supplies can't even match this stability! This is just the kind of voltage stability that the latest graphics cards require for trouble free operation.

Efficiency Testing

Efficiency tests are performed by measuring the wattage consumed by the power supply at the mains against the power (in watts) consumed by the OC3D power supply stress tester.

The results may not be as accurate as those produced by professional testing equipment, but will certainly come in handy when comparing several power supplies against each other.

Booster X3 Efficiency

The Booster X3 300w was placed under a load of 240 watts. This counts for a total of 80% of the power supplies rated output. At this load, the power supply required 286 watts from the mains to produce the 240 watts required by our custom made power supply tester.

Therefore the efficiency of this power supply can be found by a simple equation: (240 / 286) * 100, which works out to be an efficiency rating of 83.9%

Noise Testing

As previously said in the review, the Booster X3 utilises 2x 40mm fans manufacturered by Protechnic Electronics. Unfortunately i have been unable to find any specifications on these fans, so rather than discussing figures lets take a look at (or listen to) the fact.

Under idle conditions the Booster X3 produces a silent hum which i'd estimate to be around 20-24dBA. With the unit installed inside my case, the noise level was reduced slightly to the point where it could barely be heard over the case fans.

When placed under load, the speed of the cooling fans increased dramatically causing the noise levels to also increase. After around 30 minutes at load I'd estimate the noise level to be around 33-35dBa. Smaller diameter fans are well known for producing a high pitched 'squealing' and this was certainly present in the cooling methods adopted by the Booster X3.

FSP Booster X3 300w 12v PSU Page: 5

FSP have recognised the problem many people have been experiencing with SLI / Crossfire power issues and tackled it head-on. The Booster X3 is an excellent idea, and allows you to continue using you existing power supply without lagging behind (no pun) in the graphics card world.

With voltage fluctuation of only 0.4% when placed under 80% load, the Booster X3 provides more stable rails than a lot of high-end power supplies which is testament to FSP considering the size of the unit.

Let down by only its noise levels under load, and its slightly high price tag of £64 over at Microdirect, the Booster X3 is still a cheaper and easier alternative than to upgrading your existing power supply.


It may also be worth noting that there is no technical reason why the Booster X3 couldn't be used to power a Peltier, and would actually work out as a cheaper alternative than a dedicated Peltier PSU.

+ Stable power (only 0.4% fluctuation)
+ Good efficiency
+ Innovative solution for GPU power problem
+ Allows you to keep your existing PSU for longer
+ Could be used to power other devices such as a Peltier.

- Noisy under full load
- PCI-E cables cannot be plugged in seperately.
- Slightly expensive


Thanks to FSP Group for making this review possible.

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