Corsair TX750 Power Supply Review

New 320GB hard drive: $110.00
4GB of RAM: $150.00
GeForce 8800 Gaming Card: $279.00
Getting invited to the biggest LAN party the west coast has ever seen: Priceless.
What all this means: Jack shizzit if you don’t have a good PSU.

• Guaranteed rated specs delivered at 50º C
• 80%+ energy efficiency at 20%, 50% and 100% load condition for less heat generation and lower energy bill
• Active Power Factor Correction (PFC) with PF value of 0.99
• Dedicated single +12V rail offers maximum compatibility with latest components
• Supports the latest ATX12B v2.2 and EPS12V 2.91 and is backwards compatible with ATX12V 2.01 systems
• High quality Japanese capacitors provide uncompromisable performance and reliablity
• Powerful +5Vsb rail with 3A rating
• Compatibility guaranteed with dual GPU configurations
• Auto switching circuitry provide universal AC input 90-264V
• Over Current /Voltage/Power Protection, Under Voltage Protection, and Short Circuit Protection provide maximum safety for your critical system components
• Dimensions: 5.9”(W) x 3.4”(H) x 6.25”(L), or 150mm(W) x 86mm(H) x 160mm (L)
• MTBF: 100,000 hours. This thing is going to last for a long freaking time.

Included Connectors

• ATX 24 Pin & 20 Pin Compatible (x1)
• EPS/ATX12V 8-4 Pin (x1)
• PCI-E 6 Pin & 8 Pin compatible (x4)
• SATA (x8)
• 4 Pin peripheral (x8)
• Floppy (x2)

But who the hell uses a floppy anymore? On with the story and into the box, on which you can find all the above information just in case you don’t believe me. The PSU itself is surrounded by a cocoon of protective foam. Remove this and you will see a very nice black velvet bag with the silver Corsair logo imprinted on it. Inside that you will find the beautiful flat-black TX750 in all its splendor. Also included in the box is an AC power cord for getting juicetricity to your PSU, a User’s Manual, and a small baggy of screws and tie straps to make sure your cables are properly tied back for better airflow throughout your PC.

The TX750 includes a 140mm fan on its bottom, as I previously noted, and mesh on its rear. Normally we would see an 80mm fan or even smaller. But using a bigger fan, which can spin at lower speeds than a smaller fan and still have better output, and putting it on the inside of the case rather than outside lowers the noise level while greatly improving the airflow. You should also note that the 140mm fan does cause this power supply to be about ½” longer than a standard ATX power supply with a 120mm fan.

It has two standard consumption features, Active PCF and High Efficiency 80%. This means that 80% of the power yanked out of your wall outlet will be put to good use, while 20% will be wasted. By most PSU standards, this is a very nice ratio. Active PFC (Power Factor Correction) provides better use of the power allowing Corsair to sell the TX750 in Europe. Unlike other PSU’s with PFC, this one doesn’t include a 110v/220v switch on the back.

And now to the connectors. The mobo connectors enable you to power just about any board you want, from AMD to Intel. This means that no matter what board you have, and even if you are a complete novice when it comes to the insides of your PC, you can rest assured that this PSU will work for you.

There are four 6-8 pin video card connectors included as well. Any 6-pin can be turned into an 8-pin, meaning that when you throw out that old video card that has the resolution of a dot-matrix printer, you will be able to connect that ungodly expensive one with no problems. Just plug in that extra connector, and you are set.

I do have one pet peeve when it comes to the connectors. At a rating of 750W, much larger wires should have been used. The wires on this particular model use 18gauge wiring. The higher the number, the thinner the wire. And in my personal view, 18gauge isn’t thick enough. Don’t get me wrong, I’m not saying this thing is going to melt down, but the obvious factor should have been there when they designed the damned thing that when you jack up the power, use a bigger cable. Okay, I’m done ranting.

And now for the guts. It’s time to take the PSU apart. This voids your warranty, so don’t do it. That’s why I’m doing it for you… Moron. Inside, if you look right there on the Printed Circuit Board you will notice the company logo, CWT. The unit was actually built by CWT, the same people who also build PSUs for Thermaltake. But don’t get discouraged over my Nancy Drewness, this is still a Corsair through and through, and a very reliable piece of machine power.

The PSU’s filtering stage is beautiful, with the basic components used, along with one extra X capacitor, four extra Y capacitors and one extra coil. This power supply also features an X capacitor after the rectifying bridge. An interesting feature is the fuse is inside a fireproof rubber enclosure, so in the chance that the fuse should blow, the rubber would contain any issuing sparks that might set the unit on fire. Every coil in this unit is also protected by the same fireproof coating.

The thermal sensor used on this power supply is attached to the secondary heatsink. The purpose of this sensor is shutting down the power supply in case of an overheating situation and also controlling the fan speed according to the power supply internal temperature. Nippon Chemi-Con capacitors are used. As advertised, Corsair/CWT used top-quality Japanese capacitors in this PSU. The VX550 employs a slightly smaller 330uF Nippon Chemi-Con primary. The other components and heatsinks used appear to be sized appropriately for the rated output of this PSU. The heatsinks appeared to be top quality aluminum tightly squeezed in between all the other components, but with that huge fan on top and the plastic deflector directing the flow of air I see no problems with the placement of the components.

On to the test drive. The machine I used to run these tests is as described:

• AMD Athlon™ X2 Dual-Core Processor
• 4GB Elixer System Memory
• 500GB Seagate SATA HD
• Nvidia GeForce 8800 Graphics Card
• LiteOn DVD Multi-Recorder
• One 120mm fan in the front and rear of the case

In a room that was pretty stable at 65º F, I let my computer boot up and idle for around 20 minutes to achieve the idle temperature. ATX specification states than any of the +12, +5 and +3.3V rails should not be any more than 5% out of specification. A voltage reading on the +12V rail should be between 11.4 and 12.6V. Anything higher or lower is out of specification and could potentially cause system instability, or worse, damage hardware.

A quality PSU should provide output at or just slightly above the expected value. Generally speaking, a PSU is more likely to have its rails ‘sag’ when load is placed on them—i.e. during gaming or when the CPU cores are heavily utilized. It is important that voltage measurements be taken at system idle (for a reference point) and then compared to measurements taken during heavy system load. This is important to paint an accurate picture of the PSUs ability to keep voltages in check and to ensure that it is able to reliably power an appropriately sized system. Base measurements were taken at idle before doing simulated load tests with a digital multimeter.  Wattage from the wall was measured using a P3 Kill-a-Watt meter.

Here is the results of testing under Low, Medium and High load conditions:

I can honestly say that I’ve never seen a power supply with such a high efficiency under low load.  Nearly 90% efficiency is in the realm of Star Trek.  Even under moderate and heavy load, this PSU is able to maintain a high 85% efficiency rating, well above the 80% that “green” PSUs shoot for.  None of the lines were undervolted at all, but some of the rails were slightly overvolted.  Even still, the 5v line is within 2% tolerance, even under heavy load, and the single 12v rail stays within 3% tolerance.  Overall the Corsair TX750W is rock-solid stable.

In addition, the quality of this PSU doesn’t break the bank, either.  If you compare prices you will see that there are some 750W power supplies around $100, but if you look closer you will see that these are lower-quality units.  Good quality units like the OCZ Pro Xstream (reviewed here) and ThermalTake Toughpower (reviewed here)hover around $150.  The Corsair TX750 can be had between $100 and $150 from various online shops, which makes this awesome power supply a great value, too.

In my opinion, the good people at Corsair have done an amazing job of creating a solid PSU that is up to just about any challenge. With little variance and a great deal of technology and intuitive design, the TX750 from Corsair is a rock solid investment for your PC. Now that really is priceless.