Corsair TX750M PSU Review

A PSU is the beating heart of any PC. Does the Corsair unit keep the blood pumping or end in a cardiac arrest when placed under load?

Product on Review: Enthusiast Series Modular TX750M
Manufacturer and Sponsor: Corsair
Street Price: £83.99

Any system builder worth his salt will tell you that the single most important component in a PC is the power supply unit. Common sense dictates you could have the most powerful setup imaginable but without a PSU it serves no purpose other than being a very expensive ornament. Strange than that a PSU is often overlooked and yet if one was to scour any enthusiast forum, a faulty PSU is the mainstay of many troubleshooting issues.

Corsair have been expanding their product range to include PSU’s and over the years have gained a very enviable reputation by producing some very capable units. There range has now expanded to five sections, each with a range of power output. The Builder series focuses on the basic, entry level requirements while at the top of the tree we see the Professional Series Gold. Today however we have a unit from their mid-range ‘Enthusiast Series’, itself having a variety of PSU’s ranging from 550W to 950W. We opted for the 750W which finds itself in the middle of the pile and is likely to appeal to those looking for the performance you would expect from Corsair but also keeping a tight hold of the purse strings.

The Corsair TX750M as the ‘M’ suggests, is a modular unit by design utilising a single 12v rail and brags an 80 PLUS Bronze certification. Corsair’s RMA procedure is second to none and thus this PSU also grants piece of mind thanks to the 5 year warranty should you have the misfortune to encounter difficulties with this unit.

Here’s what Corsair have to say about their product:

Corsair Enthusiast Series™ power supply units are designed for hardcore PC gamers, performance enthusiasts, and anybody who appreciates a combination of high performance standards and affordability. Enthusiast Series PSUs are 80 PLUS® Bronze certified, and are available in both modular and non-modular configurations.

Based on the award-winning Enthusiast Series TX V2 line, Enthusiast Series Modular PSUs add a modular cabling system for improved installation flexibility. It provides a great combination of exacting performance standards and affordability.

Let’s first take a look at the unit specification…

Specification & Features

Features

Warranty: Five years

Dimensions: 150mm(W) x 86mm(H) x 160mm(L)

Power: 750 Watts

80 Plus: Bronze

ATX Connector: 1

EPS Connector: 1

PCI-E Connector: 4

4 Pin Peripheral Connector: 8

SATA Connector: 8

Floppy Connector: 2

MTBF: 100,000 hours

Enthusiast Series Modular TX750M Specifications

– A dedicated single +12V rail offers simple configuration and maximum compatibility with the latest graphics cards and other components

– An ultra-quiet, 140mm double ball-bearing fan delivers excellent airflow with exceptionally low noise levels by varying fan speed in response to temperature

– Complies with the European Union ErP Directive (2009/125/EC) so the power consumption of the whole system, in either standby or off mode, can be less than 1W when used with a properly configured, ErP-compliant motherboard
80 PLUS Bronze certified, delivering up to 85% energy efficiency under real-world load conditions

– Active Power Factor Correction (PFC) with PF value of 0.99

– Universal AC input from 90~264V

– Over-voltage, under-voltage, over-current, and short circuit protection provide maximum safety for your critical system components

– High-quality capacitors provide uncompromised performance and reliability

– A five year warranty and lifetime access to Corsair’s legendary technical support and customer service
Safety Approvals: cTUVus, CE, CB, FCC Class B, TÜV, CCC, C-tick

Packaging & Contents

Box Front

The Corsair unit is presented in a rectangular box and is satisfyingly heavy which is a good sign for a PSU. The outer box is typical Corsair themed packaging and shows a close-up of the unit’s main cooling fan hidden behind the grill. The 80Plus certification badge is joined with the ErP and Corsair’s own 5 Year Guarantee stamp of approval.

Box Rear

At first glance the rear of the box goes into great details until we realise that the details is actually in multiple languages meaning you only get a brief rundown of the product specification and features. This brevity is however joined by efficiency and noise reduction curves.

Inner Box

A sign of a quality product is its packaging. The Corsair does not disappoint here as there is a box-in-a-box which furthers the products protection. Opening this box we were impressed further due to the main unit being held firmly in place by a stiff foam frame which should be enough to ensure the product reaches you in perfect condition.

Accessories

Further to the product packaging, the main power supply unit is clothed in a luxurious faux velvet drawstring bag, a very nice yet surprising touch as we are not familiar with this kind of attention to details at this price point in the market.

The main unit is joined by an AC power ‘kettle’ lead, modular cables, warranty guide, safety information booklet and two baggies containing 10x zip ties, 4 hex screws and a Corsair badge.

Modular Cables

Here we see a glimpse of the modular cables which coupled with the fixed unit’s armoury of connectors makes up the following cable arrangement:

While being classified as a modular PSU it is far from 100% modular with the majority of cables being fixed. I would have opted to have seen less fixed cables and more modular cables as this would have given the PSU more flexibility and assisted in keeping the cables tidy. Nevertheless, the additional cables offer a good range of options and it was certainly nice to see the addition of Molex to floppy cable adaptors included as the floppy connector can either be a Godsend or a hindrance depending on your PC specification.

Closer Look

Overview

The main unit looks very attractive in a deep grey textured paint job. The top panel has a cut out for the cooling fan which is shielded by the grill which complements the ridged lines of the power supply unit casing nicely. The PSU top looks very similar to the BeQuiet designs which is no bad thing as the styling is discreet yet distinguished.

Modular connections

As previously mentioned, the modular connections are a little lacking on this unit with only four options available. Clearly there is room for more connections but Corsair didn’t feel that more cables were necessary in a mid-range unit.

Vents

The hot air generated from within the PSU will be exhausted to the rear of the PSU where you will find both the input power socket from the mains and the power switch. Sadly there was no diagnostic LED to be found here.

Specifications

The specifications of the PSU we discussed earlier are to be found on a sticker beneath the PSU. As you can see, the vast majority of the PSU’s output is dedicated to the 12v rail with a theoretical total of 744W.

20+4 pin ATX connector

Like most modern PSU’s, the ATX 24pin is split into a 20+4 configuration allowing for backward compatibility to the 20 pin sockets. The 20+4 pin connectors mate together by sliding one into the other ensuring a stable, secure fit is attained. Unfortunately, the individual coloured cables can be clearly seen so those who have aesthetics high on their agenda may wish to purchase a braided extension cable.

PCIe (fixed) cables

Speaking of braiding, the modular cables are fully braided but sadly the fixed cables are only part braided and do not go all the way to the plug which was a shame, especially if you are averse to multicoloured cabling. The SATA modular cable on the other hand has 100% black wires which look so much better.

Let’s crack open the enclosure to see what is hidden inside the PSU…

Internals

Dual Ball Bearing Fan

For cooling the unit down, Corsair have chosen a Yate Loon D14BH-12 which has specifications of 12V, 0.7A pushing 140CFM at 48.5dBA under maximum load. In testing the fan was very quiet only becoming a murmur under load conditions which in all honesty would perhaps be inaudible in an enclosed unit with system fans.

Exposed Unit

The platform hails from CWT (Channel Well Technology) rather than the Seasonic units Corsair are more commonly associated with. Unlike higher powered units, the TX750M has much smaller heatsinks which are notable by their omission of fins to increase the surface area cooling.

Transient filter

Transient filtering comes courtesy of two Y and one X cap at the AC input and is furthered at the front of the PCB with yet two more Y caps, an X cap, twin coils and a MOV, which is good to see as without a MOV, serious damage could occur to your PC if you don’t have the benefit of a surge protector!

Electrolyte Capacitors

Scattered throughout the power supply unit’s PCB are electrolytic capacitors, all of which are manufactured by Nippon Chemi-Con which should assist in smoothing the power delivery of the Corsair unit.

While I was initially surprised not to find any evidence of Over Current Protection (OCP), thankfully Over Power Protection (OPP) or Under Voltage Protection (UVP) should kick in should things go awry and save your setup (and hopefully your PSU) from certain doom.

Let’s move on to our testing methodology and results…

Testing methodologies & Results

Our testing methodology for testing Power Supply Units is limited to the multi-meter to show each rails performance due to us not having access to an ATE load tester. We are making plans to invest in equipment as we were directed by Cooler Master when Simon visited their test labs in June 2010.

Although this does constrain us slightly we can still monitor fluctuations on the rails and give the unit a good assessment when we feature it in one of our builds. The way the testing will run is simple, voltages will be observed at idle wattage and then a single GPU will be installed within the system and a combination of Prime95 and MSI Kombustor will be executed to provide simulation with just 1 GPU. This will be run for 20 minutes. The CPU will also be overclocked to 4.5GHz to maximise power consumption and strain. This should give us a good indication of how the Corsair TX750M will perform under gaming stresses and beyond.

Power Supply – Corsair TX750M 750W
Motherboard: ASRock Extreme4-M X79
CPU: Intel Core i7-3960X Extreme Edition
Graphics Card: NVIDIA GTX560Ti
RAM – 16GB (4x4GB) Corsair Vengeance (Red) DDR3 @ 1866MHz 9-10-9-27
Hard Drive – Hitachi SATA II 250GB
Samsung F3 1TB
Cooler – Corsair H100

I deliberately chose the HD6990 as being a dual core GPU it was the most power hungry card we have ever had at Vortez. AMD actually recommend a 700W PSU for this graphics card so it will be a close run thing. Hopefully the Corsair power protection will kick in long before we destroy the test rig should the power draw become too much although going by past experience, GPU manufacturers do exaggerate the PSU requirements somewhat.

For voltage tolerance levels, ATX specify that a 5% variable fluctuation is acceptable. (Form Factors – ATX Specification PDF – Page 10). So what this means is:

3.3V Rail – 3.135V – 3.465V acceptable
5V Rail – 4.75V – 5.25V acceptable
12V Rail – 11.4V – 12.6V acceptable

Idle test – The system settles in windows without any applications or stressing
Combined load – Prime95 + MSI Kombuster simultaneously

As you can see from the image above, at both idle and load all the lines were well within ATX specification and only drooped ever so slightly under 92.6% (695W from the wall) load. Using a multimeter to measure the voltage is quite obviously not the most efficient manner in which to thoroughly measure a PSU’s capability but I believe we have given a true reflection of its ‘real-life’ capability today.

Let’s move on to the conclusion where the Corsair TX750M receives both criticism and praise in equal amounts…

Conclusion

The Corsair TX750M power supply unit we have tested today was impressive for a mid range PSU. Powering an Intel’s latest and greatest setup in an overclocked condition along with AMD’s most powerful graphics card is no mean feat yet the PSU did so with breathing space to spare. There are however plus and minus points to owning the PSU so before we get to the good, we’ll serve up the bad news first.

If I had to pick one major gripe with the PSU it would be the amount of flexibility it offers. While it is advertised as modular it is far from 100% modular. I can forgive the 20+4 pin and a PCIe cable being pre attached as everyone will need these regardless of the setup used (assuming you prefer ad-hoc GPU’s to on-board of course). What is less easy to live with is that there’s both SATA and Molex cables also fixed in place. SATA I can understand but many people now have no need for Molex so that is one cable that will be required to hide. To compound the flexibility problem there is a distinct lack of additional cables which may prohibit what cables you attach and what you don’t . IF Corsair were worried about the number of devices being attached, we would have preferred fewer connections on a cable but more cables which in turn would enhance the flexibility of the TX750M.

The cables themselves were of average length (24pin = 55cm, 4+4pin = 62CM, PCIe = 60cm) but sadly many of the cables were not fully braided to the plug which leaves the unsightly coloured cables on-show. The braiding itself is not dense weave either and while this is not unusual for a PSU, it is an area that could be improved. If I am being particularly choosy, the blue plugs do nothing for the aesthetics of the unit being that it is mainly an orange and black affair so the choice of blue for some of the connections seems an odd one to make. It would have been nice to see Corsair incorporate a diagnostic LED with their units too. While this feature is one most often seen on the high end Enermax PSU’s it is an invaluable indication, especially when a fault occurs which in turn allows the user to decipher if it is a PSU issue or a fault elsewhere. At this price point though it is understandable one wasn’t included.

Now for the good: The packaging and presentation of the Corsair TX750M was very good and perhaps akin to a product costing significantly more than the £84 asking price. Aesthetically, the power unit is pleasing to both the eye and the touch. While I have criticised the braiding of the cables above, the main unit is attractive enough with its matt dark grey appearance and glossy black fan grill. The Yate Loon fan hardly raised a murmur under load and could not be heard over the system fans under load conditions. Better still, at idle it was silent. I do like the approach Corsair take with (some of) the cables being black, specifically the wires. These are easy to hide and are also more flexible than braided cables making cable tidying/hiding much easier. I particularly liked the idea of separate floppy/Molex adaptors which I hope is copied by all PSU manufacturers, these too made use of black wires to match the unit. Of course, looks are nothing without the performance of the PSU and here’s where the unit impressed most.

The Corsair unit coped with a huge amount of load from what we would describe as a high end system and it did so quietly with no issue at all. The voltages did drop ever so slightly under extreme load conditions but were always well within ATX specification. Clearly the unit is not built for quad GPU monster folding systems but for a mid range system, multi GPI configurations would still be within the performance remit of this PSU. While the PSU is a classed as a modular unit, I would tend to consider it as a unit with fixed cables that offers some modular capability. The ultimate in flexibility it is not but if you are in the market for a mid-range PSU which will power mid-high end system then the TX750M is certainly worthy of consideration. Sure it has its faults but if you can live with them then you have a very capable unit. Sadly though, other than the floppy-Molex adaptors there is nothing here which makes the PSU stand head and shoulders above the competition in what is a very highly contested market segment. I was therefore stuck on whether to give the TX750M our stamp of approval or the bronze award. After careful consideration I’m going to award it both as despite its drawbacks it does what it claims to do and does it very well.

Pros
+ Good packaging
+ Quiet
+ Good performance
+ 5 Year Warranty
+ Reasonable Price

Cons
– Barely ‘modular’
– Cables not fully braided