Greetings, readers. It is another fine day here in the jonnyGURU.com labs, which look suspiciously like a basement with bad carpeting, and I have something special for you today. That's right, today I am going somewhere I haven't gone before. No, I'm not talking about the shower. I'm talking about load testing something huge, something at the very limits of what the lab gear is capable of. Today's review is of the Silverstone Strider 1500 watt unit.

Like most Silverstone units, our would be 1500 watt space heater has most of its marketing hype right on the front of the box:

• 100% modular cables with cable bag
  -100% modular is very nice. However, as we saw with last week's Ultra X4 review, the extra ATX connector can sometimes present voltage drop issues if we run the 3.3V and 5V rails too hard.
• 1500W continuous and 1600W peak power
  -Folks, I might as well fess up right now. I can load test up to and beyond 1600W. But there's a problem in that my power measurement devices only reach to 1850W at the wall. Since I don't put much stock in peak numbers anyway, I hope y'all don't mind if I stop at a mere 100% of full load this time as I do every time.
• Efficiency 85%-88% at 20%-100% loading with 80 PLUS Silver certification
  -This kind of efficiency is pretty much necessary to get this kind of power output and still get a pass from the UL for North American operation. Yes, there is a more powerful unit out there than this one, but it only reached approval by offering two power cords: one designed only for 20A outlets, and one with a 15A circuit breaker for normal outlets. Otherwise, there would be no Ultra X4 1600W.
• Class-leading eight +12V rails with 110A (Peak up to 120A)
  -That's a lot of rails, but then again 110A is a lot of power. That's 1320 watts for the 12V rails alone... more capacity than a 1200W unit could manage with all the rails going at once. We'll see if these rails are sensibly distributed a bit later on.
• 1500W continuous power output with 40°C operating temperature
  -Uh, Silverstone? My hot box is ruthless when it comes to units this big. I can pretty much guarantee it will exceed 40 degrees, even with all three auxiliary 12V loaders helping out with some of the load. I'll just have to see how this bad boy handles the heat.
• Strict ±3% voltage regulation
  -While not that impressive, keep in mind this number is being applied to something powerful enough to almost require its own circuit breaker back at your house's breaker box to get to full power. Three percent is not that impressive any more when you're talking about a 1kW unit, but this unit is five hundred watts more capable.
• Silent Running 135mm fan with 19dBA minimum
  -Sorry, but I don't have the facilities to test these claims. But if you like, I'll whistle Mike + The Mechanics songs all review long again. You say you'll shoot me if I do? Well... ok. I'll spare you just this once.
• Japanese main capacitors
  -Ah, but what of the secondary capacitors?
• Four PCI-E 8pin, eight PCI-E 6pin, and 12 SATA connectors support
  -Huh... I could have sworn I saw a VGAx3 logo on the front of the box. This little blurb would have me believe this monster can take four high power video cards. And so it should... what else are you going to need to power with a 1500W power supply?
• Support ATX 12V 2.3 & EPS 12V
• Active PFC

Ah, good. Silverstone has come through for us once again by confirming that the black unit pictured on the box really is black. 4.2kg? Are you serious? That's almost ten pounds of power supply! Ooh, look at that little load table there... 12 volts at 25 amperes times eight. That should do the trick, depending on how it's split up.

In case you're not able to read the marketing hype in English, Silverstone has once again decided to accommodate you. On this side of the box, it's all repeated in nine different languages.

Except for the spec manual for the 1500W model being up front and center in this shot, you wouldn't know that a 1500W unit lurks below that sheet of white foam.

And there you have it - the contents of the box. There are two manuals, a modular cable bag, a 14 gauge power cord, two PCI-E dual 6 pin to one 8 pin adapters, some zip ties, some velcro ties, some thumbscrews, some regular screws, and some modular cables. I think that's it. That is, except for the Mall of America. Oh, wait, that's not a mall, it's a power supply. Wait here... I'm going to go inside and buy a CD. There's gotta be a music store in there somewhere.

The two user guides didn't come alone, they brought a friend - a little sheet of paper that says this power supply is capable of drawing lots of current, and that you should use only the power cord included and avoid use of an extension cord. And they are correct in saying this. If it's putting out 1500 watts, it's going to be pulling in a fair bit more than that, even with 80 Plus Silver certification. That's assuming this sample can hold to the certification... we'll find out soon enough.

A quick look at the spec manual, which gives you just about every spec on this unit you could want.

The installation manual is pretty much the same thing Silverstone throws in with a good many of their upscale units. It's a very nicely done, not to mention thick, affair with lots of pictures and multiple languages.

Continuing on, here's a picture of an industrial AC unit... I mean, power supply. Wow, that's a big one. See that little white speck there on the top? The one you can just barely make out against the massive expanse of blackness? That's the fan hub. Okay, okay, I'll stop with the hyperbole. On page two.

Meantime, we'll take a look at the back of our Silverstone minivan. Gosh, I love matte black, but I could do with fewer stickers on the surface with the fan on it.

Well, it looks like we can't just use any old power cord anyway. This unit uses that special C19 connector we saw on the Strider 1200W model. As was also the case on that model, there is no power switch... almost every inch of free space on the rear panel of this unit is needed for ventilation.

What's that little metallic sticker, you ask? Why, that's the sticker that tells you the modular cable interface is licensed from its patent holder, Ultra Products. Kind of sticks out on this unit, doesn't it? Kind of like that big stone chip in your car's freshly painted headlight door cover that you got because the highway department thought it was a jolly good idea to dump gravel all over a well traveled paved highway where nobody ever slows down.

With apologies for letting Mr. Fuji get dust on his lens, here's the top panel of the unit, with Silverstone's logo embossed on it. Why couldn't we have put the stickers here? Won't this panel go unseen in most cases? Wouldn't an embossed Silverstone logo look better on the football field stretches of metal bracketing the fan on the other side of the housing where we can see it?

As if the 12V capacity of this unit wasn't somehow enough, this unit carries with it a seriously powerful combined 3.3V/5V rating of 280 watts. While this is intended more to make sure that your two tons of hard drives and gobs of memory have enough power to run, you could also use this unit to power that old Duron rig you're building for that kid down the street. Of course, you'd then be wasting serious amounts of 12V potential.

Speaking of potential, did you spot the 5VSB rating yet? Yup, this thing can manage 6 amperes on that rail. For most systems not named Phobos, this is a massive amount of overkill.

For those anxious to find out who built this unit, it's Enhance. That makes three OEM's now that I know of who have PS2 sized units of greater than 1400W currently on the market, the others being Channel Well Technology and Andyson; though you can't get the CWT PUC based model in North America due to them not passing the UL certification stage. The Andyson model? That would be the Ultra X4 1600W.

Here are the modular cables for you in one big table covering mess.

The modular connectors. Fear not, for the EPS12V connectors will not interchange with the PCI-E connectors.

Is the 12V distribution sensible? Why, yes it is. Each of 12V5 to 12V8 is dedicated to one chain of PCI-E connectors. Each of those rails gets one 6+2 pin and one 6 pin connector. Enough for four cards. And with a 25A limit on each rail, it is very unlikely you'll run into the overcurrent protection, even with the most powerful cards now on the market. And if you do, with four 12V rails dedicated to only PCI-E connectors, you can always start combining, as this unit draws its 12V water from one big pool.

Of the rest of the 12V rails, two are dedicated to the EPS12V/ATX12V cables alone. That's 50A for the CPU... just try and use that up, I dare you. The remaining two are for the ATX and peripheral connectors, with one of the four peripheral connectors on 12V3 and the remaining three on 12V4. You're probably not going to use up that combined 50A either.

And now it's time to get down to brass tacks. And once I use those brass tacks to put this Star Trek poster back up on the wall, I'll get started with the load testing. Ah, there we go... all better.

For those of you who are new to the site, my load testing gear centers around a SunMoon SM-268 automated test environment. It's a fancy electronic load that can load these here power supply thingers in precise combinations all the way up to a thousand watts or so. But, this is a 1500 watt model, so the 268 will be joined by some friends - three 240 watt supplementary 12V electronic loads. This is only the second time I have needed all three of them running at once, and with them and the 268 combined, I can load up to about 133A of 12V capacity. To the four electronic loads I will add some other gadgets, including a Brand 4-1850 power meter, a multimeter, a USB oscilloscope, and a dual probe thermometer.

Loading for this unit will be decided by the maximum rated specs on the label, except for the "peak" rating. Since this is an octuple 12V design, and I can only scope four rails at a time, I'll be summing them all down to one big 110A monster.

Testing will go in several stages. First, a set of five balanced and progressive load tests followed by two lopsided crossload tests at room temperature. That will tell us what the unit can do in general. After this, I'll run a low load test to see what the unit's efficiency looks like below the minimum 80 Plus load. Following that, I'll go looking for turn on spikes that are out of spec, like I usually do. And last but by no means least, I'll lock the Strider in the hot box and see if it can still do 1500 watts when the heat comes on.

Let me just get this out of the way right now: the ST1500 can go from 22A on the 12V rail all the way up to 110A with only a 0.15V drop on those combined rails. Forget 3% regulation, that's almost 1%. That is exceptional considering the difference in loading is over a thousand watts. We're off to a fantastic start here.

Moving over to the two minor rails, things are wilting just a little bit where the 3.3V rail has dropped out of 3% and the 5V rail is just barely within it. While that is somewhat disappointing, consider this - both of those rails saw an unrealistic 17A load by test five. You would likely not see this too often in normal use, even on a unit this size. That said, we can likely put this down to the fully modular cabling on this unit. You may recall that I saw similar voltage drops on the Ultra X4 last week due to the connector pins being somewhat looser than they could be. This is about the only time modular cabling can be considered a detriment to performance. Still, with the regulation staying well within the ATX spec of 5%, it's not that much of a detriment.

Taking a look at the efficiency numbers, we can just go right ahead and say this unit passes Silver certification levels. No, it's not quite there in test five, but remember - this is a 1500W unit pulling 1747 watts out of a Brand meter with a 2% accuracy spec. That's good enough for me, and we still get that magic 85% number if we round off. And look at test CL2, the heavy 12V crossload test. To get 89% efficiency in that test is simply astounding, given the 110A 12V load there. Folks, this is what you can expect from this unit if you only have a couple hard drives and four video cards running full out on this thing... almost Gold levels of performance due to the minor rails not bringing down the efficiency.

So, we have some awesome performance so far from one of only two 1400W+ units currently available on the North American market. But you know what? The awesome does not stop with the voltage regulation or efficiency. Take a look at the temperature readings. Most of my big Enhance based review samples have had a major problem with heat to the point that the overtemp protection shuts them down in the hot box. But, this unit doesn't seem to be doing too badly, for a change. Yeah, it was getting up there by test five, but I actually have hope that this unit will pass the hot box without issues now. Remarkable, considering that this isn't just any big ol' Enhance, it's a 1500W King Kong Enhance.

Usually, I choose a 10% load level for this test as it's more often than not a good look at what you'd be seeing with the computer idling at the desktop. In this case, however, 10% is still 150 watts. So, I went with 7% this time. Now, the nature of the SMPS beast is that the lower the load level, the less efficient they are. On this unit, we still get 77% down there at a 105W load. That number may not sound too impressive considering that it is below 80% on a Silver certified unit, but I can't help but be somewhat impressed anyway - at a 7% load level, most units start to really fall off the efficiency trolley. I'm going to call this very good performance.

Overshoot Transient Testing - Silverstone ST1500
VSB On	VSB to Full 12V	Off to Full 12V

Moving on down to the overshoot transient tests, there's more good news. You'll recall that ATX spec allows for these spikes to be no greater than 10% above mean value. In the above shots, every green line is 5 volts. You know what that means? Right... on this unit, the 5VSB rail is spiking below 4 volts and the 12V combined rails are staying below 9 volts. This is with the unit at a 100% load... in other words, the unit was set to test five up there. 110A on the 12V rails, and 6A on the 5VSB rail. This is not the best performance I've seen, but it is very, VERY impressive considering we're load testing Godzilla's own power supply today.

And now we get to the fun part - the hot box testing. My hot box is an old ATX case that has been modded to have the entire heat output of the SM-268 channeled into it, and is just barely large enough to hold a 220mm deep power supply; as my pinched fingers can tell you. Since about half of the 12V capacity on this unit is offloaded to the auxiliary electronic loads, this box won't get quite as hot as it would otherwise. Make no mistake though, it will be heating up good. So, I'll turn on both the intake and exhaust fans to try and get as close to that 40 degree operating temp spec as possible.

But enough about the hot box. Let's cook us a Sears Tower... er, I mean a Silverstone 1500 watt power supply.

Ok, I'm just going to tell it like it is. It's awesome. For the first time ever, a 1kW+ Enhance build has not shut down on me in the hot box. It simply did not care that the hot box got hotter than forty. It just kept on pouring out the juice like it was still at room temperature. And it was only putting out 62 degree air at the exhaust. That is just outstanding, people. And it was doing all this with a fan I couldn't hear at all. Granted, I had seven other screamers running at the same time, but I really expected to hear this thing really crank up the fan by test five, and it just didn't seem to need to. Happy with this, I is very.

But that's not even the best of it. Yes, you're looking at 1% regulation on the 12V side now. Yes, 3.3V and 5V regulation is now better, with both now holding 3%. And yes, the unit almost did Silver again, just missing it by a hair... in the hot box! Very few of my review samples have been able to hit their certifications when the heat comes on, and the ST1500 has come closer than most to pulling it off.

I am very impressed so far, folks. Let's look at the scope shots and see what a 1500W unit's ripple suppression is like.

Oscilloscope Results - Silverstone ST1500
Test #	+3.3V	+5V	+12V
Test 1
Test 2
Test 3
Test 4
Test 5
Test CL1
Test CL2

I'll confess that one part of me would like to see better 12V ripple suppression than this. But another, much more vocal part of me is reminding me that we're looking at less than 80mV on a unit that is putting out 110 amperes of 12V current. Honestly, I'm not sure how much better performance we can expect, here. I mean, what's the competition? Where is the competition? You have the Ultra X4 1600W, and you have nothing else if you live on the same continent I do. The Enermax Galaxy Evo 1250W? Well, I suppose you could go with that one if you felt like stopping at 104A of combined 12V capacity and never making it to 1500 watts. Certainly, that one did have better 12V ripple suppression at full power. But look at test four up there... that's a 1200W load, and ripple suppression is every bit as good there as seen with the Galaxy.

And before you wave the fact that this unit was only doing 88A there in front of my face, look at test CL2's results - that's 1313 watts (calculated) and 110A on the 12V rail, out of reach for the Enermax. And we only get 50mV of ripple there. We might as well face it, this is one incredible power supply.

Time to take this unit apart and see what a 1500W monster looks like on the inside.

Hmm, I must have gotten the wrong side of the fan. Yong Lin? They must mean Young Lin Tech.

Yup, that's what they mean all right.

Man... that's a lot of power supply to take apart. And look... there are two fins with heatshrink! That usually means both a fan control thermistor and an overtemp thermistor on these big Enhance units. Since overtemp is not specified in the spec manual, and I couldn't get the unit to shut down in the hot box, we can only speculate on whether or not it's really there. But I'll tell you this - OEM's rarely throw in stuff like this if they can save a buck by taking it out.

AC transient filter starts at the AC receptacle, as usual. Two X caps, two Y caps.

PCB soldering is neat and clean. Not the best ever in the whole universe, but well above average.

Good golly, it still looks like a mall with the heatsinks out. I think I see an Ikea over there on the left. There's more transient filter out front, consisting of a MOV, two coils, two Y capacitors, and two X capacitors. A pair of GSIB2020 bridge rectifiers are attached to those small heatsinks there.

Primary capacitors are all Nippon Chemi-Con. All four of them.

Secondary capacitors are some seriously tall Teapo parts.

Why self, I say, it looks like there are four filter coils on this bad boy. What's the extra one for? Well, self, I'll tell you. There is one for the 3.3V, one for the 5V, and two for the 12V. The two big transformers are connected in parallel to save space, and the double 12V coils negates the need for one big coil thus saving more space. Why, self, that makes a lot of sense! Doesn't it, though, self? What's that metal heatsink up by the primary caps? Well, self, that's for the PFC diode. It's so massive, it needs a heatsink of its own. That heatsink in turn is bolted directly to the main primary heatsink for extra cooling.

This is the back of the modular cable PCB. Unlike certain other units I reviewed last week, the workmanship is actually tolerable.

The other side of the modular cable PCB has some extra filtering for the 12V rails.

And here we have the primary heatsink. On the left are the main switchers - two 32N50C3's powered by a UC3715 chip. On the right are the PFC transistors - three 47N60C3's. Main PWM controller is a good old CM6800G.

Finally, here's the secondary heatsink. One MBR1660 rectifies the 5VSB rail. One STPS40L45CW and one IRF4104 handles the 3.3V rail. 5V is done with one IRFB3206 and two IPB041N04N parts. Finally, the 12V output is provided by five IRFB3206 parts in parallel. The unit uses synchronous rectification.

Performance (40% of the final score) - now how do I score something that is seriously lacking in North American competition? I suppose I'll just wing it. This is a 1500W unit, rivaled by only one other power supply on this continent for sheer output capability. This is a power supply that was able to hold its own with the Enermax Galaxy Evo in terms of ripple suppression until it went and passed the output capabilities of said Enermax. This is a unit that put out some hundred and ten amperes of 12 volt current, all while regulating within 1% in the hot box. This is a unit that would not shut down in the hot box, even when confronted by temperatures well in excess of the specified operating temperature. When you get right down to it, this is quite simply the most awesome Enhance built unit I have ever seen, and in my view it is more than worthy of this here 10 I'm giving it.

Functionality (20% of the final score) - what more can a guy ask for here? This unit has all the cabling one could ever need for anything short of a thirteenth SATA device. But you know what? Those SATA connectors are 250mm apart on their cables. You could easily add more if you wanted. But that's also where the ST1500 comes up short... in those long 250mm stretches of cable. Like all big Silverstones, those connectors are all just too far apart for me. So, I'll have to go down to a mere 9 here.

Value (30% of the final score) - this is going to be a tough one. Why? Well... there's no real competition other than the big Ultra unit. This bad boy is currently going for $362.99 at Sundial Micro. The older Ultra X3 1600W can be found at just under $300, but that's only because the X4 is out now, and that X4 is currently not any cheaper. That's not even mentioning the fact that I don't currently know how either Ultra performs compared to this one. Really, if you need something this powerful, you can't do better for this price, at least not right now. 10.

Aesthetics (10% of the final score) - as usual, I love the matte black. But, I'm going to remove a point for the sticker frenzy on a surface I could see through the window of my Twelve Hundred, and for an embossed Silverstone logo I couldn't see in any case I own. 9.

Summary

I've been waiting for a long time to say this - Silverstone has a real honest to goodness class leading winner here. Not only is the ST1500 the second most powerful unit you can buy in North America as of November 2009, but it's among the best performing units I've tested at any level. Ripple and noise was well in check, efficiency was flat out awesome, the unit ran cool, and the unit ran quiet. Though not many people will ever need the amount of power this monster puts out, even as a 1200 watt unit it stands out. What are you waiting for? Go buy one.

The Good:

• exceptionally powerful
• highly efficient
• very good ripple and noise suppression
• no shuttie downie or death even with temps well over 40 degrees at full power
• enough cabling for four video cards, and they all get a 12V rail to themselves

The Bad:

• too long cable stretches between Molex/SATA connectors

The Mediocre:

• nothing at all