Zalman ZM750-EBT PSU Review

[Guest]

Zalman's new EBT line consists of four PSUs ranging from 650W to 1kW capacity. Today, we're testing the ZM750-EBT, which, thanks to a low price, achieves a good value score. But how does it fare in terms of absolute performance?

Zalman ZM750-EBT PSU Review : Read more

 

[Onus]

Although the article does mention safety, a very valid point, it still managed to imply that a single-rail PSU was "better" due to the complexity of managing rail assignments so as to not trip OCP protections. I've have not seen a multi-rail PSU actually get dinged for this in a review for maybe 8-10 years; it seems that everyone does OCP "right," so this is no longer an issue, ever. That being the case, the greater safety of a multi-rail design is superior.
I'll need to make at least another pass through this article, but failing on +5V ripple under heavy load probably makes this a solid tier-3 unit; I'm not going to run screaming if I see one, but I wouldn't buy it either.

 

[JQB45]

Tier-3 might be generous. There were a lot of cons. What good is a 7 year warranty if the PSU takes something else out in addition to the PSU.

CONS: Ripple • Noisy under stress • Hold-up time • Inrush current • Sleeve-bearing fan • Single EPS connector • Inaccurate PWR_OK signal

Also it must also be strongly pointed out that this unit does not meet ATX specifications.

 

[Onus]

True, but the tier-3 units are the ones considered solid for lighter loads. Those cons are why I certainly would not buy one for a gaming or rendering rig, but for the typical PC that may not need even half this power, I wouldn't worry about it.

 

[Sakkura]

The fact that it's not just barely breaking the ATX spec at 100% load, but already starts to go out of spec at 80% and then has two rails well out of spec at 100%, is what makes this a tier 4 unit, and a clear "do not buy" regardless of price.

 

[yyk71200]

One would expect that a gold rated powersupply would be at least a solid unit and a safe buy. Guess not. Shouldn't buy one simply based on advertised efficiency rating.

 

[Onus]

That's definitely true. Coolermaster taught that lesson quite well.
Hmmm, this one does seem a little worse than I thought at first. Any chance this particular unit had a problem? I'd think ripple could be fixed with a minor capacitor improvement, without adding too much to the price. Hopefully Zalman is paying attention.

 

[JQB45]

That's definitely true. Coolermaster taught that lesson quite well.
Hmmm, this one does seem a little worse than I thought at first. Any chance this particular unit had a problem? I'd think ripple could be fixed with a minor capacitor improvement, without adding too much to the price. Hopefully Zalman is paying attention.

agreed

 

[COLGeek]

It is interesting to see Zalman developing this line of PSUs. Hopefully, they will be better than previous generations. Had a couple Zalman PSUs a few years ago, when I used to use Zalman heatsinks.

One died days after the warranty expired and the other about a month after. I'll give Zalman credit, they made right by me by exchanging both, but it was a painful process.

While I would not recommend these current products, I can at least "tolerate" them in budget builds.

 

[turkey3_scratch]

I would think anything out of spec should be Tier 4. Ripple is trash. 3.3V rail was on the brink of being out of spec. 12V was also quite terrible at 90mv.

Anyway, I like your power supply reviews, Toms. You go more in-depth than any review site for power supplies (Hardwaresecrets, Johnnyguru).

 

[Sakkura]

That's definitely true. Coolermaster taught that lesson quite well.
Hmmm, this one does seem a little worse than I thought at first. Any chance this particular unit had a problem? I'd think ripple could be fixed with a minor capacitor improvement, without adding too much to the price. Hopefully Zalman is paying attention.

Considering the same platform performs decently in the Silverstone unit, there's at least some hope that Zalman can go back, adjust a few things, and get a decent budget unit out of this.

Edit: I went back and looked at the Silverstone review. Ripple suppression was really good up to 90% load, then the 5V and 3.3V rails jumped hugely, especially the 3.3V. They did stay within ATX spec, but just barely. The 5V ripple went from 13.1mV at 90% to 40.5mV at 100%, 3.3V ripple went from 14.1mV at 90% to 49.9mV at 100%. Obviously the 3.3V ripple went out of spec at 110% load, as well as one of the crossloads, but that's a lesser sin.

 

[Novuake]

Saw heading, got excited, read article, disappointed.

Damn it Zalman, I expected good things!

 

[Compuser10165]

From the bunch, I'd take an EVGA SuperNova G2 anyday over those PSU's (including the Zalman) (I personally have the EVGA 850 G2). The build quality is outstanding as well as the voltage ripple, very good efficiency. Also, in terms of aesthetics it is much better: all black, all black cables, fully modular.

 

[Compuser10165]

From the bunch, I'd take an EVGA SuperNova G2 anyday over those PSU's (including the Zalman) (I personally have the EVGA 850 G2). The build quality is outstanding as well as the voltage ripple, very good efficiency. Also, in terms of aesthetics it is much better: all black PSU with nice texture, all black cables, fully modular. One thing to note though: My particular PSU had two threads not straight so I had to screw 2 of the screws holding the PSU at an angle (the PSU mounting mechanism was the culprit). The bother is only aesthetic, though