Death of a Gutless Wonder V: Uncool to the Max

Once in a while, it’s good to take a break from all the fantastic units companies send us and have a look at the stuff they won’t send us. Today’s unit comes from a company that quit sending us review samples when my load tester revealed the terrible truth about their then-new 950W beast. Folks, let’s torture a Coolmax ZX-500 and see what happens.

PROD LINK: ZX-500 Product Page
PRICE: $34.99 @ NewEgg
Price is at the time of testing!

Well, well, well. Look who’s dropped in to see us today. The last time I took a look at a Coolmax unit, it was way back in 2008 and we shook our heads in utter disbelief as the CUG-950B completely fell on its face. Since then, we haven’t received a single review unit from Coolmax, presumably out of a dawning realization that this here website tells it like it is when it comes to these power supply thingamajiggers.

But one day earlier this year, I woke up thinking, “what if things have changed at Coolmax? What if they’ve gotten better?” I decided that in fact, I wanted to give them another shot. After all, six years have passed. Surely, things have improved since then. But how to do it when I don’t get review units from them anymore, and can’t afford to buy one? The good Muddocktor from our own forums was the answer to my prayer, and he graciously offered to buy one for me.

And that brings us to the above image. Our review sample is the extremely low-cost Coolmax ZX-500. What better way to see if Coolmax has turned the corner than to look at the real bargain-basement stuff? This is an 80 Plus Standard 500 watt unit, and we’re going to see what it can do.

Now, don’t get me wrong. Back in the day, Coolmax was pretty much like most other companies. They had their bad units like the CUG-950B or the CUG-700B that literally tried to pop a cap in my backside, but they also had rather good units like the CUQ-1350B. This is not the worst power supply company I’ve dealt with, in other words. And even that 950B was a half-decent unit… to a point. It’s just that the marketing people and/or the “powers that be” over there were a little too gung ho to impress the public by slapping numbers on their units that were out of touch with reality.

And what does the marketing on this unit tell us so far? We have us a power supply certified by 80 Plus. And this unit is listed there, so we know already we should get at least full power at room temperature because that’s how you earn a pass at the 80 Plus labs. We know this unit has a double ball bearing fan, single 12V rail, active PFC, and several protection circuits.

I’m having trouble with the Crossfire/SLI bullet point, however. At 500 watts, you’d need some crazy low powered cards to work with this unit. Especially since this side of the box claims only two PCI-e connectors.

Limited 2-year warranty. Folks, that should raise a red flag for you, whether or not the unit is decent. You should ask yourself what about the warranty is limited. And why is it only two years? Most power supply companies either do the bare minimum of one year, or go three years to match the majority of the competition. Two years is just odd like they’re only expecting these to last that long. I’m going to be taking a hard look at the electronics side of this thing on page five – I’ll let you know on that page how long you can expect this model to last.

We’re not done with our retail box yet. This side of it bears a big graph letting us know what the fan curve is, and gives us some basic specs.

READ ME FIRST. There is no manual in this box – go to our website to download it. Ok, Coolmax, I’ll play your little game. It’s probably some basic little one-page thing that… wait… oh, wow. Coolmax actually did a fantastic job on their manual for this unit. It’s not the best I’ve seen, and it’s not long, but there are more specifications in this document than a lot of more expensive units.

That said, I see a huge red flag in there as I find out that this unit is only rated to full power at thirty degrees. It de-rates to 90% at forty degrees, and 80% at fifty. I don’t like this. Do you have any idea how easy it is for the inside of your case to pass thirty? It ain’t hard, people. Personally speaking, my hot box is very unlikely to make this unit happy. The overpower protection will have to be working very well indeed if this unit expects to live through this day because at this price point you usually don’t get overtemp protection.

Assuming we get to the hot tests at all, that is. The cold tests are already quite demanding on these extreme bargain units.

My advice, though, if you want something to last a long time? Pass on any unit you know that is rated to thirty, or not rated at all. I don’t care if it comes from FSP, Corsair, Antec, Coolmax, or out of the back of a Chinese white van in Shenzhen. Units with temp specs that low are pretty much an admission by the company that the wattage number on the side is going to be really hard to attain in everyday use for a lot of people. You don’t want them to hit full power in Texas when the air conditioning fails, in other words. Any decent unit is going to be fine at forty degrees, with fifty being the target for the industrial-grade bad boys like last week’s AX1500i.

Inside the box, we find only two items: a power supply and a power cord. There are no zip ties, no case stickers, no modular cables, no cloth bags to store things in. This will cost the unit in functionality scoring, but this is not a bad thing when it comes to bargain units. If it comes down to skimping on the power supply guts or the accessories to get a unit into a certain price point, I’d rather see a good quality power supply and nothing else in the box.

On that note, you know you’re in trouble if you just bought a 500W unit for forty bucks and the box is crammed full of extra goodies.

So far, I’m cautiously optimistic. Page two, if you please.