Coolmax CUG-700B 700 Watt Power Supply

The quest for higher efficiency and environmental friendliness has led us to the Coolmax Green Power CUG-700B 700 watt power supply today. Will our review sample herald in a new era of stability and efficiency? Come inside and see.

PRODUCT: Coolmax CUG-700B
700 Watt Power Supply
PRICE: $129.99 @ NewEgg
Price is at time of testing!

I have a confession to make – green is my favorite color. Fortunately for me, a lot of things in this world are green. Why, take my desktop for instance: the mouse pad is green, my screwdriver is green, my wallet is green, and this cheese I got out of the fridge is green. Wait a second, maybe I shouldn’t eat that.

Something else in my house is green today, if the box it came in is any indication: the Coolmax CUG-700B. And so, with much rubbing of my hands in anticipation for all the cool greenness contained within this box, I hereby declare today’s review underway.

Coolmax CUG-700B 700W

The Coolmax Green Power series, according to the back of the box, consists of two models… the 700W we are looking at now, and a 600W model. Both boast triple 12V rail topology, with the only differences in the specs being on the 12V rails. Since triple 12V topology is a mite unusual for a high power unit, I immediately began to look forward to getting a peek inside to see how many 12V rails it really had.

Except for a couple of cool little logos claiming RoHS compliance and Intel/AMD dual core support, the front of the box is pretty uncluttered and tasteful, I daresay.

Coolmax CUG-700B 700W

On the side of the box, we can see a long statement on how this power supply meets RoHS compliance. Then, we see a great big long list on what Coolmax claims is not present in the unit. While I suppose it’s nice to know what’s not in the box, I was getting anxious to see what WAS in there. After that list, I wondered if perhaps the power supply had been replaced with a nice, safe, RoHS compliant block of wood or something. But I turned the box around again to see what else was printed on it, confident I would in fact find a power supply within.

Coolmax CUG-700B 700W

It’s a little hard to read this, so I’ll type out some of the highlights:

  • triple 12V output rails
  • advanced double forward circuit and double layer PCB
  • active PFC
  • Super high efficiency [sic] maximum 84%
  • Ultimate balance between cooling and noise level
  • Dual PCI-Express power connectors fully support SLI & Cross-Fire system
  • Gold plated terminal

There are a few more less interesting bullet points on the box, but I think I got the more relevant ones covered. I can’t wait to see which terminal is gold plated. What’s on the side opposite the big RoHS compliance statement? Why, another long RoHS compliance blurb I’m way too lazy to type out here. Or get pictures of. Time to open the box and unleash the greenness within.

Coolmax CUG-700B 700W

Coolmax CUG-700B 700W

I call false advertising! That power supply isn’t green at all! The big white box just behind the power supply is the first thing you see when you open the lid, and it contains the modular cables. The black box holds the power cable and mounting screws. Finally, we see an owners manual with so much information contained within that I’m certain you could almost build one of these Green Power units from scratch. OK, let’s have us a table wherein we can see all the numbers being promised by this PSU.

Coolmax CUG-700B – DC Output
DC Output +3.3V +5V +12V1 +12V2 +12V3 -12V -5V +5VSB
28A 30A 16A 25A 17A 0.5A N/A 2.5A
Max Combined Watts 180W 500W 6W N/A 12.5W

I must admit, the triple 12V topology is weird all by itself. But the numbers up there make it all the weirder – why not even out the specs, instead of giving 12V2 so much power compared to the others? Despite the otherwise complete information in the manual, it was not immediately clear what rail went where. Some connectors were specified as being on +12VDC with no number to signify which one, while others like the SATA connectors claimed to be on +12V3DC. That’s a little odd, and I think I’m going to be taking this apart after the load testing to see what the real story is.

Coolmax CUG-700B 700W

Coolmax CUG-700B 700W

But first, a good shot of the modular cables and the end of the power supply you plug them into. All connectors are Molex Mini-Fit Junior type, which are fairly reliable. Those two little two pin connectors are supplementary 3.3V connectors for the SATA cabling, which uses a combination of these connectors and the four pin connectors next door to power the SATA connectors. At this point, you might be thinking to yourself, hmm… I see three different colors, could that be how the three 12V rails are split up? I’ll answer that later, I promise.

In the meantime, let’s throw together a nice table with a rundown on the modular cables and how long they are. The manual helped me get really lazy here, by telling me exactly how long each cable was. I just copied it all down.

Coolmax CUG-700B – Cabling
Type of connector:
ATX connector (550mm) 20+4 pin
2 x 2 12V connectors (550mm) 1*
2 x 3 PCI-e (550mm) 2
8-pin Xeon/EPS connector (550mm) 1*
6-pin Xeon/AUX connector 0
5.25″ Drive connectors (550mm + 200mm + 200mm) 8
3.5″ Drive connectors (+200mm) 2
SATA Drive power connectors (550mm + 200mm) 4
Fan only connectors (thermostatically controlled 12V only) 0
*8 pin EPS connector splits apart

Now that the preliminaries are done, it’s time to make the doughn… er, test the power supply. Yeah, that’s it. We don’t need no doughnuts. I’ll be right back. I’m not going out for pastries, honest.