I’m back at it again! This time it’s a Thermaltake Smart 730 W PSU that I’m torturing. The Smart series promises solid performance for a low price. An entry level buyers dream! The question of the day is: How’s the performance? We’ll see.
Features and Specifications
As usual we’ll start with the marketing. Also as usual, it comes direct from Thermaltake.com. By “as usual” I mean it usually comes directly from the manufacturer. If I’m reviewing an Antec unit the info doesn’t come from Thermaltake.com. For a Thermaltake unit it does though. If you think I’m wasting your time rambling, you’re right. It could be worse though, you could be one of the editors who has to read this and check it for grammar and punctuation!
- Guaranteed to deliver 730 W continuous output @ 40 °C (104 °F) operating environment. While most power supplies work well in optimal conditions Thermaltake ensures the SMART Series power supply can operate efficiently even in the higher temperatures found in the computer chassis.
- Robust and dedicated +12 V rail delivers up to 56 A to ensure your components get the power they need whenever they demand it.
- 80 PLUS® certified: with 82-86% efficiency allows the SMART Series power supply to deliver full power while also saving cost on your utility bill thanks to the high efficiency power design.
- Double-forward switching circuitry offers low power loss and high reliability.
- Active Power Factor Correction provides clean and reliable power to your system.
- Ultra-silent operation with intelligent 12cm cooling fan with active speed control to ensure even under the heaviest load the SMART Series power supply will stay cool and stable.
- Intel® & AMD multi core CPU compliant.
- Nvidia® & ATI/AMD graphics card compatible.
- Dimension: 150 x 86 x 140 mm (W x H x L).
- Built in industrial-grade protections: Over Current, Over Voltage, Over Power and Short-Circuit protections ensures that your components have many safeguards against possible power problems that could otherwise damage your expensive hardware.
- Safety / EMI : TUV, CE, UL, FCC, BSMI.
Here we have the large block of text in which I look at the marketing and add my comments. Can you skip this? Absolutely. Should you? I have no clue. Will you regret skipping it? Maybe. In any case, 730 W at 40 °C is the first claim, that will be tested. A single 12 V rail is cheaper, but not necessarily better. 80Plus is nice, Bronze would be nicer, but 80Plus is a good start. Double forward switching was snazzy some time ago, now it’s fairly basic. It does work well, though. APFC is nice for your utility company and nice for you in that it can soak up small surges without issue. It also allows you to plug the unit into 90 VAC to 220VAC without changing a switch. It has nothing to do with the power the PSU puts out though. Ultra-Silent is like saying “Less Nothing!” or “More Infinite!”. Something is either silent or it isn’t, and given that this unit has a fan it is not silent. Ultra-Quiet maybe. Compliant with All the Things! One hopes. OCP/OVP/OPP/SCP sounds nice. I’m checking SCP these days, so this unit had better hope it really has SCP. (I bridge the PCIe 12 V and GND planes in my tester).
On to the specifications! Most of them, anyway.
Intel ATX 12V 2.3
Max. Output Capacity
Peak Output Capacity
86 x 150 x 140 mm
Power Good Signal
16 msec (minimum) @ 50% load at 230 Vac 50 Hz input.
12 A – 6 A
|Input Frequency Range|
50 Hz – 60 Hz
100 Vac – 240 Vac
+10 ℃ to +40 ℃
20% to 85%,non-condensing
-40 ℃ to + 70 ℃
5% to 95%, non-condensing
120 mm Fan: 2000 RPM ± 10%
80% efficiency @ 20-100% load
100,000 hours minimum
CE, TUV, FCC, UL, BSMI
Ignore the peak output capacity, it’s fairly pointless. Other than that, the only thing of note here is that this is a fairly compact PSU. That’s nice.
Thermaltake thoughtfully provides an output table as well:
|Input Voltage: 100 V-240 V|
Input Current: 10 A-5 A
Frequency: 50 Hz-60 Hz
|Max Output Current|
|Max Output Power|
For a non-DC-DC PSU this unit can do an amazing amount of 12 V, very impressive. Actually putting out that much means a fairly heavy crossload, we’ll see how well it survives that in testing.
Lastly, Thermaltake gives us a chart of the protection trip points. This is quite rare and I appreciate it. I’ll also check it against the protections IC datasheet to make sure it’s correct. Look for that in the Dissection Section.
Over Current Protection
Over Voltage Protection
Under Voltage Protection
Protection Point (Max.)
Protection Point (Max.)
2.0 V~2.4 V
3.3 V~3.7 V
8.5 V~9.5 V
|Short Circuit Protection: Activated when any DC rails short circuited.|
|Over Power Protection: Protection at 110%~150% full load.|
The OCP trip points are reasonable, the OVP/UVP trip points are… dubious. Looks like a PS232S protections IC to me (note: I have not opened the PSU yet. It’s a guessing game at this point), not my favorite, but better than nothing.
Now that we’ve read all the marketing, let’s look at the marketing on the box!
Photos Part One: The Box
In these modern days of online purchasing, the outside of the box really isn’t that important. Either more computer parts are sold at brick and mortar stores than I think, or companies haven’t realized that they can stop spending so much money on packaging prettiness.
Without (too much) further blathering, here’s the box. I like the box, it’s tastefully decorated without going overboard on anything.
The packaging isn’t overly long on protection for the PSU, the bubble wrap does the bottom, one side and the top. Bubble wrap and cardboard does the exhaust grill, while bubble wrap and the power cable do the other side. The top gets bubble wrap and some manuals. It seems to work well enough, this is the fifth of the Smart series that I’ve looked at in my career and all have been intact after shipping.
Photos Part Two: The PSU
Now we get to see the PSU itself! Well, now you do. I already saw it.
The PSU itself looks pretty good, it’s a half-shiny half-matte sort of finish, with decent looking labels. Impressively, it’s shorter than it is wide, nice for cramped cases. The cables are short on sleeving, but we’ll look at them in the next section. For the moment, here’s the rest of the PSU:
If you look closely at the grill shot, you can see a transient filter inductor leaning back. Either it’s dancing to a fairly terribly song from the last decade, or someone wasn’t as careful as perhaps they should have been when they installed it. We’ll look more closely in the Dissection Section.
Lastly, a few angled views so you can pretend the PSU is in a RPG or something.
Photos Part Three: Cables
Thermaltake thoughtfully provides a list (with photos!) on their product page. I’m thoughtfully putting it here so you don’t have to count the cables in my pictures.
Pretty decent selection for a 730 W unit. Plenty of PCIe cables, that’s a plus as many 750 W units only have two for some strange reason. Four Molex connectors, a FDD connector, and eight SATA connectors round out the accessory bits. We have a 20+4P motherboard power connector and a 4+4P CPU power connector. Perfect. The pictures above aren’t actually of this specific PSU though. For pics of this unit, scroll down.
Sleeving exists only on the motherboard cable, this is unfortunate from a looks standpoint. The +2P of the PCIe power cables could use one more cable tie to keep the second +2P somewhere in the area of the 6P it goes with. Not a huge deal, but annoying.
Lastly, we have the accessories bundle. This consists of a power cable and four screws.
It’s not the best accessory pack in the world, but it’s far from the bottom. If you stray too far into the budget PSU world, you don’t get a power cable or screws!
Time for testing! That’s where things get real.
Testing Part One: Regulation Testing
A decent load test of a PSU requires a decent load. Contrary to what some may believe, that means you need a known load that can fully stress the PSU. Computer hardware does not cut it. Worse, if the PSU fails during testing it might take out the computer hardware anyway. Commercial load testers cost a lot of money. I do not have a lot of money, so I built my own with juicy power resistors and a Toyota cylinder head. It works great. I’ll be using it to load this thing down fairly severely and will check voltages and ripple (more on that later) at various points. The down side to my tester is that the loads it can put on PSUs are fairly coarse, they go in increments of 48 W for 12 V, 50 W for 5 V and 22 W for 3.3V. Those wattages assume the PSU is putting out exactly the official rail voltage, a PSU putting out 12.24 V rather than 12 V will be at 49.9 W per step rather than 48 W. I file that under the “tough beans” category as I figure if a percent or two of load makes that much of a difference, the PSU manufacturer should have hit the voltage regulation more squarely. It does make calculating efficiency difficult at best. However, given that the input power is read via a Kill-a-Watt, the efficiency numbers are dubious to begin with. Kill-a-Watts are not known for extreme accuracy on things with automatic power factor correction. For this reason, I am not listing the efficiency.
The ATX spec says that voltage regulation must be within 5% of the rail’s official designation, regardless of load. It doesn’t actually mention that the PSU shouldn’t explode, though I expect they figured it was implied. Exploding is a failure in my book regardless.
It is also worth knowing that I will be testing this PSU at both outdoor ambient temperatures (typically between 10 °C and 20 °C here this time of year) as well as in the Enclosure of Unreasonable Warmth. TEUW is a precision engineered enclosure that I use to route the exhaust air from the PSU right back into the intake fan, it is adjustable to hold the intake air temperature at (almost) any level I want it. This way I can test the PSU’s response to hot conditions as well as cold conditions. For the hot testing I will be running the intake temp as close to the unit’s maximum rated temperature as possible. TEUW, in case you’re curious, is a cardboard box.
|Wattages (total)||12 V Rail||5 V Rail||3.3 V Rail||Kill-A-Watts||Air temp in/out|
|672/50/0w (722w) 12V-CL||11.77||5.01||3.40||879||10/24|
|TEUW 40c intake air results are below|
|672/50/0w (722w) 12V-CL||12 V OCP triggered|
As you’ve probably noted the bottom line there aren’t numbers. This is because at the max rated temperature of 40 °C the PSU would shut down when the final 48 W of 12 V load was applied. If removed it would happily turn right back on, but no matter what connector I put the load on, it wouldn’t take it. It would accept 760 W of load if I put the rest on the 5 V and 3.3 V rails so it wasn’t OPP. Given the numbers Tt specs give for OVP/UVP it wasn’t that either. 12 V OCP it is! On the plus side, this implies that it won’t explode if overloaded. On the negative side, it’s a ~620 W 12 V unit rather than the 672 W 12 V the box and PSU claim.
On the matter of regulation, this is clearly a group regulated unit. It doesn’t appreciate crossloads overly much, but does significantly better on them than some units I’ve seen. The 12 V rail comes in at 4%, the 5 V rail comes in at 5.5% and the 3.3 V rail comes in at 8%. If I chuck the extremely rude crossload result for the 3.3 V rail, it gets 6.3%, which is better but still pretty bad. On average (throwing out the zero 3.3 V load result) we have 5.26% regulation. Not terrible, but not exactly good either. On the plus side the unit can cough up full wattage at 40 °C for a sustained amount of time, and the fan is on the quieter end of things even at full load and 40 °C.
Testing Part Two: Ripple Testing
Ripple is fluctuation of the PSU’s output voltage caused by a variety of factors. It is pretty much impossible to have zero ripple in a SMPS computer power supply because of how a SMPS works, so the question is how much ripple is there? In the regulation testing phase we found out how the PSU does at keeping the average voltage at a set level, now we’re going to see what that voltage is doing on really short time frames. The ATX spec says that the 12 V rail cannot have more than 120 mV peak to peak ripple, the 5 V and 3.3 V rails need to stay under 50 mV.
If that isn’t complicated enough for you, there are three forms of ripple to keep track of as well. Long-term ripple from the PSU’s controller adjusting the output voltage and over/undershooting, correcting, overshooting, etc. Medium-term ripple from the voltage controller charging and discharging the inductor(s) and capacitor(s) that make up the VRM, and very short-term ripple caused by the switching itself. The first and second forms are the most important, if they are out of spec it can cause instability at best or damage in extreme situations. The very short-term (I call it transient ripple) flavor is less crucial, excessive amounts can still cause issues though it takes more of it to do so. The ATX spec does not differentiate, as far as the spec goes 121 mV of transient ripple is just as much of a failure as 121 mV of medium or long term ripple.
I test ripple in a few difference ways, first I test it during the cold load testing. It is tested at zero load and maximum load first. During the hot load testing I test the ripple at maximum load again. I have recently started testing ripple at fairly random loads with the unit still hot, it’s a bit unorthodox (a bit? maybe a lot) but has found issues in the past that did not show up with other test methods.
We’ll start at zero load and cold temperatures and work our way up from there. In all shots the scope is set to 5 ms / 10 mV.
The 12 V rail looks excellent, the fan’s motor coils firing are the cause of what little ripple there is. Interestingly, the same is true of the 5 V and 3.3 V rails! I locked the fan so it couldn’t start, no ripple. Allowed it to turn and the ripple came back. Weird, but whatever. 6 mV is great for 12 V. The 5 V and 3.3 V results are OK. Zero load is a dubious test though, let’s try 100% load.
48 mV on the 12 V real is good, well below max spec and better than some units that cost a lot more. 22 mV on the other two rails is pretty good, too. The shape of the 3.3 V ripple is very strange indeed, I have no clue what’s up with that.
Now with a very heavy 12 V crossload, still cold intake temps, scope still at 5 ms / 10 mV.
No issues here, all three rails are right around 50% of the maximum spec, that’s just fine. Now for some hot results at full unit load.
With the unit hot, the 12 V rail has the same amount of ripple, the 5 V rail drops 1 mV and the 3.3 V rail drops 5 mV. Other than that pesky 12 V load shutting the unit down when hot, this unit is happy there.
All told for this section, ripple control is good. No issues here at all.
Disclaimer: Power supplies can have dangerous voltages inside them even after being unplugged, DO NOT OPEN POWER SUPPLIES. It’s just not a good idea. Opening a power supply and poking around inside could very well kill you. Don’t try this at home. Don’t try this at work. Just don’t do it.
First up, the fan hub and an overview of the interior, much like I saw when I definitely didn’t open this unit at home.
The fan connector was glued, this is a nice touch. Also nice (for me at least) are the spade connectors for the incoming wall power. The only thing really of note we’ll be seeing next in the transient filter section anyway. I’ll talk about it there.
Welcome to the transient filter section! The transient filter mops up the generally messiness of the incoming wall power and restores a nice clean sine wave. It starts at the receptacle with a PCB that has two Y capacitors and an X capacitor, then it continues on the main PCB with three inductors, a fuse, a TVS diode for surge protection, two more Y capacitors and another X capacitor.
See the inductor on the left? It’s leaning rather heavily! Based on the glue across the top (for stability and noise control) it looks like it was initially in the correct place. Sometime after that something happened. Either it got dropped in shipping or someone grabbed the wrong bit of it. Which one it is, I can’t say. It worked fine bent over like that though, it doesn’t matter electrically. The transient filter is nice and complete, no issues here.
Next up we have the APFC section, it starts by rectifying the incoming AC to DC and then boosting it to ~380 V and stashing it in a nice big fat capacitor. This is the capacitor that can lay you out if you open a PSU. The rectifier is a GBJ1506 (15 A, 600 V). There are three MOSFETs on APFC switching duty, all three are 6R190C6 (20 A @25 °C, 13 A @100 °C, 650 V) units. The boost diode is a BYC10600 (10 A, 600 V). The storage cap is a Teapo 400 V 105 °C unit. Controlling the operation is a FAN4800IN APFC/PWM controller.
As you can see above, the two primary switches are more 6R190 MOSFETs, these are E6 rather than C6 for whatever that is worth. The voltage and amperage specs remain unchanged.
On the secondary side, the 12 V is rectified by four 40L60CT (40 A, 60 V) Schottky diode packs, while 5 V and 3.3 V each get two 30A40CT (30 A, 40 V) Schottky packs. Output capacitors are all 105 °C Teapo parts. People like yelling at Teapo due to the issues in the early 2000’s on Dell motherboards (and some others). In PSU situations, Teapo caps work just fine.
The PCB is short on UL numbers, it looks like a HEC / Compucase piece. The case has UL number e199442, which links to Compucase. That answers that question!
Interestingly, this appears to be a dual rail PSU. Not only are there two colors of 12 V wiring, but the PCB is marked for 12 V 1 and 12 V 2, and beyond that the PCB has sensing bits and traces that lead to the PS223 protections IC. The PS223 (not a 232, I guessed wrong. Same protection trip points though) supports two 12 V rails, making this a dual rail PSU. It’s not often we see a dual rail marketed as a single rail, that’s new and different. I’m happy to see it, really. I have no idea what the rail sizes are. I did re-test the unit after finding this, the shutdown when hot issue does not appear to be related to the dual rail nature of the PSU. Lastly, the overall soldering is good, but there is one place where a sloppy technician had to do some manual work and didn’t do a very nice job of it.
All together this is a solid looking unit. I could do without the soldering messiness of course, but that’s a fairly minor issue. The leaning inductor is odd as well, but it’s more of a non-issue. The multiple 12 V rails is strange, but I have no issues with additional safety measures! I’m just surprised Tt didn’t put it on the label.
Final Thoughts and Conclusion
Coming into this review Thermaltake’s “Smart” PSUs have been on a pretty bad streak lately, this unit is doing its best to end that streak. It’s not a PSU that I can hold up to the sky and proclaim to be the best of all possible PSUs (I’ve yet to find that one), but it’s a solid unit.
The looks are decent. The case itself looks nice, but the un-sleeved cables offset that. The PCIe cables really need one more cable tie to keep them under control in my opinion.
The connector selection is good, there aren’t many 750 W units that have four PCIe cables. It seems to me like they all should, but many (most?) do not. This unit has four, that’s a point in its favor.
The fan is quite polite, at low through medium loads it’s very quiet and even at full blast it’s not bad at all.
The regulation is OK. I was extra-brutal in the regulation tests (for a group regulated unit, anyway), and it survived them with everything within spec. Things swing around in the good old fashioned group regulated way, but it stayed within ATX specifications at all times. On one hand I’m impressed by that given the group regulated design, on the other hand 6% average regulation isn’t exactly good.
Worse though is shutting down at the maximum 12 V load (672 W) when hot. I’d much prefer that it shut down rather than run in dangerous territory, but doing what the label says would be better. At cooler temperatures it does that load just fine. I did some additional testing and found that the line was crossed at ~30 °C intake air. Below that point it could put out the 12 V the label says it can, above that it shuts down. If I decreased the load to 624 W, it ran happily. This can’t really be taken as anything but a failure however, if it cannot do 672 W at 40 °C the label should not say it can.
On the plus side, we have two 12 V rails rather than the single on the box. I dislike the marketing fail, but I do prefer two rails to one rail.
Ripple control wise this unit did quite well, no issues there at all.
At a current retail of $85 this unit is priced a bit high. It currently comes with a $25 mail in rebate to offset that, but I’d prefer they just knocked $10 off the price. It’d be a good price at that point. As it is, it’s competing with 700-750 W 80+ Bronze units. At $75 it would be surrounded by 400 W to 600 W units and would be a good deal.
All told there are a number of pros:
- Plenty of connectors
- Nice and quiet
- Good ripple control
- Two 12 V rails
There are some cons too though:
- Shuts down with a (max 12 V load) 12 V crossload at 40 °C
- Regulation is a bit loose, though within spec
- I’d like more sleeving
- Price without MIR is a bit too high. Price with MIR is good
At the bottom line, as much as I would like to approve the unit I just can’t quite do it. The combination of a price that is $10-$15 too high (in the $70-$75 price bracket this would be a monster) and shutting down at a load / temperature combination the marketing says it can do prevents me from approving the unit. In the $85 price range there are a couple better choices. If you happen to find this unit on sale, go for it! Its largest problem, really, is that it’s on the outdated end of things. That’s okay if the price is great, but the price is not great. As such, I’m forced to apply a Meh rating. Click the Meh to see exactly what it means.
— Ed Smith / Bobnova