Although high-wattage power supplies get most of the glory, we take our hats off to small, efficient solutions offering more practical output. We take four sub-450 W PSUs and run them through our benchmark suite to see if we can determine a winner.
In the automotive world, being green is all the rage. No manufacturer wants to be caught without at least one model aimed squarely at that demographic. And sure, the government gets involved by compelling the industry to move toward cars that consume less fuel and pump out fewer emissions into the atmosphere. The response isn't surprising: our more mainstream cars trade power for higher efficiency.
The same general principle can be applied to power supplies. Today's processors are far less power-hungry than their predecessors. Even gaming-oriented PCs built for performance seldom suck down more than 450 W. Better efficiency, on the other hand, is good for both the environment and your wallet.
So, we went into this round-up with the following two requirements for the participants: their submissions couldn't exceed 450 W and they needed to be efficient. In order to keep prices within reason, we settled on an 80 PLUS Gold rating as sufficient to meet our second demand.
Technical Specifications
| Products |
CoolerMaster V4505
|
Corsair RM450
|
Enermax Revolution X't 430W
|
Seasonic S12G 450W
|
| Pricing |
|
|
|
|
| Certification | 80 PLUS Gold | 80 PLUS Gold | 80 PLUS Gold | 80 PLUS Gold |
| Dimensions (WxDxH) | 150 x 140 x 86 mm | 150 x 160 x 86 mm | 150 x 160 x 86 mm | 150 x 140 x 86 mm |
| Weight | 1.6 kg | 2.76 kg | 1.8 kg | 2.16 kg |
| Operating Temperature | 0 to 40 C | 0 to 50 C | Up to 40 C | 0 to 40 C |
| Warranty | Five Years | Five Years | Five Years | Five Years |
| Specification | ATX12V v2 | ATX12V v2.4 | ATX12V v2.4 | ATX12V v2.4 |
| Specified Power Output | 450 W | 450 W | 430 W | 450 W |
| Maximum Peak Output | N/A | N/A | 475 W | N/A |
| AC Input | 100 - 240 V | 100 - 240 V | 100 - 240 V | 100 - 240 V |
| AC Voltage Selection | Auto Voltage | Auto Voltage | Auto Voltage | Auto Voltage |
| DC Output +3.3 V | 20 A | 24 A | 20 A | 20 A |
| DC Output +5 V | 20 A | 22 A | 20 A | 20 A |
| DC Output +12 V | 36 A | 37.5 A | 35 A | 37 A |
| DC Output -12 V | 0.3 A | 0.8 A | 0.8 A | 0.3 A |
| DC Power +12 V Combined | 432 W | 450 W | 420 W | 444 W |
| PFC | Active | Active | Active | Active |
| Specified Hold-Up | > 16 ms | 16 ms | 16 ms | > 16 ms |
| MTBF | 100,000 hours | 100,000 hours | 100,000 hours | 100,000 hours |
| Fan | 120 mm | 135 mm | 139 mm | 120 mm |
| Fan Speed | N/A | Up to 924 RPM | 600 to 1300 RPM | Up to ~2100 RPM |
| 20+4 pin Motherboard | 1x (60 cm) | 1x (60 cm) | 1x (55 cm) | 1x (55 cm) |
| CPU | 1x (60 cm) | 1x (65 cm) | 1x (60 cm) | 1x (60 cm) |
| PCI Express 6-pin/6+2-pin (Graphics) | 0/2x (55 - 65 cm) | 0/2x (60 - 75 cm) | 0/2x (45 cm) | 0/2x (60 - 70 cm) |
| Molex 4-pin (Peripherals) | 3x (40 - 70 cm) | 4x (45 - 75 cm) | 4x (45 - 90 cm) | 3x (50 - 70 cm) |
| SATA Power | 6x (40 - 70 cm) | 6x (50 - 70 cm) | 8x (45 - 90 cm) | 8x (50 - 80 cm) |
| 4-pin Floppy | 1x (85 cm) | 1x (90 cm) | 1x (105 cm) | 1x (80 cm) |
| Accessories | Screws | Screws, Cable ties, Fan cables | Screws, Velcro Strips, Cord Guard | Screws, Velcro Strips, Cable Ties |
| Cable Management | Yes | Yes | Yes | No |
| Other Details | N/A | Fanless Mode | Fans run 30 to 60 seconds after powered down. | N/A |
Four vendors stepped up to our challenge. Seasonic offered its S12G at 450 W, which is currently selling for $75. Enermax sent in its Revolution X't, rated for 430 W and available at $90. Spend an additional $10 and you can get Corsair's RM450, which, as its name suggests, is rated for up to 450 W. Cooler Master submitted its V450S. And although that unit appeared promising, it isn't available in the U.S. That makes Seasonic's power supply the least-expensive option in our field, which isn't something you might have expected.

Readers have been begging for you guys to do a proper PSU test for years. I'm glad to know Tom's has taken the time to listen.
/sarcasm
It would have also been nice to see one of Seasonic's TFX units included.
I lol'd at the operational noise graph because it tells you nothing. What rail(s) are they testing? Who knows? Who cares...
You are welcome to continue to defend the article, but the truth is that nobody takes a Tom's Hardware PSU review seriously. This review doesn't do anything to change that perception. Compared to the depth of analysis that goes into other PC components, it is disappointing to see Tom's continue to ignore the requests of its readers to bring a thorough, full-featured PSU review to the table.
Yes, these are supposedly made by top-tier manufacturers, but just because they have a reputation in the past doesn't mean they have a clean slate the entire way through.
"In order to keep prices within reason, we settled on an 80 PLUS Gold rating as sufficient to meet our second demand."
I'm also happy with my 80+ Bronze P/S. Frankly, when you're buying smaller output P/S, I really don't know why anyone would need to get a Gold-rated one.
I paid like 70$ for a top of the line 660W seasonic platinum PSU after MIR. Needless to say I was patient and waited for a good deal, but I see high quality 650-750W PSUs for 80$ after MIRs regularly.
True, PSUs typically operate most effeciently at 80% load. I build gaming rigs though, so 400W is always too small.
I just expected smaller PSUs to be cheaper, that's all.
This review feels like useless. There's no ripple testing, whatever the second comment user says. Get some review from Guru3D and you'll see.
Based on words I can't compare with other products on other reviews, so this is quite a fail.
Haha... well I can beat you on your own games from my cell phone.
I agree. If I am buying a gold rated 450w unit, I am not buying any of these. I will go and get a Capstone 450w for $60.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817182066
Haha... well I can beat you on your own games from my cell phone.
Hahahaha yup, given a micro HDMI port. But I'm speaking of a machine capable of challenging the PS4. My old NES 8 bit is going to be revived with the KFA2 750Ti and an i5S processor. Actually I badly wanted the Broadwell architecture but I can't wait 2015...
The three most important things to review on a power supply are regulation, ripple suppression, and hot box stability.
My suggestion for Patrick is to go look at CRMARIS and Oklahoma Wolf's PSU reviews to see how a real review is done.
The only way to verify true quality is with hot box torture. That's how you separate the elite PSUs from the turds wrapped in a box.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139010
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139056
Unless they buy it for the rating and know nothing else about a PSU, but if you checked out the price links to Amazon, no one is that dumb to spend that much on a small wattage PSU. The CM one is sold by some unknown vender with a $44 dollar shipping! Corsair has some reviews, but that's not for the 450w, they're reviews for higher wattage models.