Check out review of Seasonic X 650W at jonnyguru.

Here's a link:

http://www.jonnyguru.com/modules.php?na ... y&reid=169

Just wow. Expensive, but initial reviews are looking really good. Can't wait for SPCR's take on this PSU. Installed in an isolated chamber, looks like this PSU should be able to operate fanless up to about 270W DC. Unbelievable.

Even in the hot box configuration, thermal performance was still very impressive.

Yes, and I am also interested in that test. I imagine others who use a UPS would also be interested. This is a "new design" and you never know...

Just a followup to my post above, I decided to ask Seasonic if there were any issues with a UPS operating with simulated sine wave, which was a question I asked Enermax and was assured there wouldn't be any problem. The fellow from Seasonic said he didn't think there would be an issue with any UPS, not exactly the answer I was hoping for. I think there should be a more definitive answer before someone using a UPS with simulated sine wave spends close to $200 dollars.

Both the X650 & X750 are both now in stock at NewEgg.

See:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151088

and
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151087

I've got an X650 on order.

Depends on who you ask.... maybe you got some low level sales guy who just gave a boilerplate answer. Maybe push to move it up a notch to at least someone in the R&D department...

Did better than that, I sent an email to Taiwan support and received nothing after at least two days. I think they really don't know, never tested it with a simulated sine wave UPS.

I read the online manual and nothing about UPS. If you read the Enermax manual, you will see it clearly stated compatible with simulated sine wave--this is the kind of information every manufacturer should provide in their manual.

This issue of compatibility with UPS is especially important with Seasonic's "new design."

If you think you can get someone at Seasonic to give a definite answer about UPS simulated sine wave, try calling or emailing them.

No way I'm going to be touching these at the price they're at. I'm expecting them to cost the thick end of £150(=$240) when they hit the UK, that's just too much money.

I've been bitten too many times by the "new hotness" thing. I don't actually care about fans in PSUs any more, they can be swapped, it's coil whine that bothers me. I also don't trust that the review samples will accurately reflect the samples sold on the open market.

I think besides of that ripple development vs. load controller IC changing operating modes is reason also for that insensitivity of efficiency to low load. (88.8% @ 10% load)


I'm not... sine wave UPS.
Mains side is still active PFC like before and components after that (where changes happened) will never see anything about line voltage waveform unless PFC/rectification fails totally.

I know, some are serious Golden Samples... but I think Sea Sonic is pretty cool about this and send production units. So I've heard. Makes no sense to get a wonderful test result on the web and then you bring it home and it sucks...

Yup, Seasonic has always been honest with samples. It's only the MD12D and X series samples that even can with any kind of "reviewer's package" which is so much the norm.

Do you use a simulated sine wave UPS? If you do, you may certainly buy the Seasonic and let us know.

I do know CyberPower and APC both say there can be issues with an active PFC unit, and CyberPower added high efficiency active PFC as another concern. Why don't you call them and ask? After all, they do represent the company making UPS and no need for them to talk you out of buying their unit.

I know one other poster who asked for a review to test simulated sine wave UPS with this Seasonic PSU--so there are others who are interested, not you, but others not so willing to chance $200 dollars.

Strange, I replied earlier to this post but I don't see it anywhere....
Anyway, I got the following answer from Sea Sonic.
Their guy said it really depends on which UPS you use because depending on the quality of the UPS will end up generating different types of Sine Wave. Perfect is of course what comes out of the wall, but if you have a crappy UPS, then you probably get block waves instead of sine waves... and shouldn't expect anything to work correctly with it...

Sounds logical.... I suppose...

This makes me wonder about the Enermax response that sure it will all work... will it all work? Is there a special technology in the Enermax unit that will make it work with even crappy simulated sine wave? I haven't heard anything about that...

As I told you previously, the Enermax manual states compatibility with simulated sine wave. Is that so hard to understand? The man I spoke with from Enermax said their previous model, an older Infinity, also active PFC, was not compatible, and he said the MODU+82 was compatible as stated in the manual. In other words, Enermax knows a bit more about their PSU's than Seasonic.

Both CyberPower and APC know a bit more about their UPS devices than you do, and I already told you what they said.

When the guy from Sea Sonic told you "it really depends on which UPS you use because depending on the quality of the UPS will end up generating different types of Sine Wave", what that means to me is he is talking simulated sine wave versus pure sine wave. Why didn't you ask that guy from Sea Sonic to clarify what he meant by that statement? Simulated and pure sine wave are two different characteristics used by UPS devices. Did you know that?

"Strange, I replied earlier to this post but I don't see it anywhere....

Now that is an intelligent response.

Oh, and by the way, I have the simulated sine wave UPS shown in my signature and it works perfectly with the Enermax MODU+82 PSU in my signature.

The question remains are the Sea Sonic X650 and X750 compatible with simulated sine wave?

The Enermax MODU+82 works without issues with simulated sine wave and that is a fact. Now go and get some facts from Sea Sonic whether or not their X series is compatible with simulated sine wave, if they know.

Hmm... it looks yummy! But the price

"A little tag warns, "Temperature Activated Fan Rotates Only When Required" — probably an attempt to stave off returns by consumers who think the fan is broken when they discover it doesn't spin upon power-on."

"The fan started spinning about 10~15 minutes into the 150W load test."

Now from review by Jonny Guru:

"Hello? Is this thing on? Such were my first words when I powered up this unit for testing. The fan twitched and immediately stopped. It didn't turn on again until test three. And then it turned off again for crossload test one. It seems that Seasonic wasn't joking about this being a quiet unit... you just can't get much quieter than fanless. I like that the fan twitches just to let you know the unit isn't dead or something."
http://www.jonnyguru.com/modules.php?na ... 2&reid=169

Mike, did you notice this "fan twitching" Jonny Guru is talking about?

You mention the P182 but what about people such as rpsgc interested with a Solo?

Nope. Does it matter? It didn''t start spinning till nearly 200W load.


The standard hot box testing result applies. Nothing special about PSU cooling in the Solo.

It's simple enough to summarize:
1) Keep the immediate temperature around the PSU to under 25C and the fan won't start up till >300W. When/if it does, it will still be about as quiet as any PSU you can buy.
2) The higher the immediate temp around the PSU, the lower the load point at which the fan will start up. It's directly tied to temperature.

All sounds very good, Mike, but I am quite satisfied at present with my Enermax MODU82+ in the Solo. However, in the future, when doing a new build, I would consider the Seasonic X series if I knew they were compatible with simulated sine wave, and I am certain others would like to know that as well.

Great review, although to me, it highlights the odd state of desktop computers nowadays. Most likely, the migration away from desktop computers towards laptops has saved more electricity than the 80Plus program could have ever hoped to save. I was going to lament that there's no good 80Plus Gold rated PS in the 300 watt range, but I realized - anybody with computing needs that low probably buys a laptop instead, and gets far lower power consumption anyway.

It's still nice to see the improvements though. Certainly for a light server box, say, a nehalem based system with a GPU and total system draw around 350-400 watts when folding would see a nice benefit from this power supply versus an older one like my S12-600. For 24x7 running at 350 watts DC, the change in A/C power would be from 432 to probably 385 watts assuming a bottom-mount case like the P180 to keep the power supply running cool temps. That's a 47 watt savings, which is 412 kw/h over the course of the year, saving maybe $40-45 in a state like mine. That's kind of cool. My S12-600 has lasted about 4 years. If you ran this new PS for 4 years then that's maybe $160-200 in savings, which would help justify the price premium these Gold units fetch.

Your comment about the temperature rating being aimed more at server-class machines may have been for that reason. That's probably the market these power supplies are aimed at, since otherwise it's hard to justify the price premium.

So spill the beans already I'm assuming the SS-550LT is the same basic PSU minus the modular cables?

Great review. Now I've got PSU envy. Regarding the pricing...I wonder how much of it is "because we can" (first to the mkt price premium) and how much is higher component costs?

Here's hoping that this is a new design paradigm to be copied by all of the other guys. With the usual drift toward mainstream pricing.

Hardware Secrets reviewwith a detailed tear down on the components used.

Hey, don't make it sound like I am trying to sell you one, I'm not. It's a review! Besides, you asked a question, I answered!

Man, JVM, had a hard day or what? Not getting enough or what?

I just thought I might be able to help but looks like you prefer to bash on me instead. Sweet! Get a life....

Hey JVM, guess what, Sea Sonic just said their PSUs have zero problems with simulated sine waves so you shouldn't worry about any compatible issues.

Feel better?

If my Phantom 500 ever dies (something I worry about occasionally) I can rest safe in the knowledge I can just replace it with this

Not until they tell me that, or put it in the manual. You spoke to them on Saturday morning.

Argument regarding UPS noted. Time to move on.

Enermax seem to be on the way with a couple of 80plus gold PSU's as well:
http://www.enermaxusa.com/support/download/2009_catalog.pdf
(First page to the left)

I have no idea as to when it will hit the market or under what name though.