Thermaltake Smart SP-850M 850W Power Supply Review

Author:Paul Johnson

Editor:Kyle Bennett

Date: Monday , June 16, 2014

Thermaltake has been hit and miss in the power supply department over the years. It has produced some excellent PSUs and some that were just "good," and others that did not meet ATX12V specification. Thermaltake comes to us today with its Smart Series PSU that touts Bronze efficiency with its semi-modular design.


The Thermaltake SP-850M is the latest power supply that we have seen from Thermaltake. Over the years, we have seen a number of Thermaltake products. Today's SP-850M is somewhat different as this is the largest capacity mainstream product we have seen from Thermaltake. Previous 850W units that we have seen have all been of the Toughpower XT line which was, at the time, on the high end of what Thermaltake was offering. So, with today's SP-850M slotting in below that product we have no previous direct comparison for this unit. As such, the we have no real idea how Thermaltake is going to do in these waters today. Will the SP-850M really be a smart solution? Of is this a product that could use a bit more studying before being released into the wild? Let’s see.

HardOCP’s testing methodology is intended to very much push power supplies to their advertised wattage rating in temperatures that will represent some of the hottest computer enthusiast cases. So if a unit passes all our testing it is definitely not something to take lightly. In fact we expect more power supplies to fail our testing than make it through unscathed.

Build Quality

The build quality of the Thermaltake SP-850M starts things off today on a better than expected note in a lot of ways. Externally, this unit is somewhat of a mixed bag but generally is well done. The unit features a decent finish, some nice embossing, a nice fan grill, and, for a semi-modular power supply, nice cabling that includes a number of FlexForce style cables. The one downside to the exterior build quality is the oddly color schemed stickers that adorn the side and front of the unit. On the upside, these are removable of course. When we move to the interior of the unit, we see that we are looking at a rather modern design from CWT that features a double forward primary paired with synchronous rectification on the secondary as well as DC-DC VRMs. While a solid topology for an 80 Plus Bronze unit, we do find a bit of disappointment that the included fan is a Yate Loon fan. That is not the only slightly lower quality item as when we look at the capacitor selection we also see a smattering of Apaq solid capacitors used. The majority of the capacitors, however, are high quality including Panasonic (standard electrolytics), Nippon Chemi-com (standard electrolytics), and Enesol (solid). The actual integration on the single layer PCB is generally well done, though not the absolute best we have ever seen. Moving on finally to the support side of things. we see that the unit ships with a 5 year warranty which is good, but the user manual is really not very good.

Load Testing

The overall load testing results for the Thermaltake SP-850M were not universally great relative to the competition. What really started this unit off on a weak footing was the voltage regulation. Here, we the 12v rail saw a peak change of 0.21v and the minor rails did better with a peak change of 0.07v. These results put this mixed to trailing the Kingwin PF-850, NZXT HALE82 850W, and the Corsair TX850 v2. Where this unit does some making up was with the efficiency which, at 83.67% to 87.71% during the 120v load tests and 80.11% to 86.64% during the 100v load tests, were actually very good for an 80 Plus Bronze power supply. Indeed, when ran the 80 Plus tests, we saw efficiency values of 86.87%-88.54%-83.59% for the SP-850M which easily put this unit right in its claimed 80 Plus Bronze category. Lastly, this unit passed the Torture Test with no real changes to speak of. So far, the SP-850M has kind of mixed bag going with the really good efficiency but not so good, but passing ATX12V specification voltage regulation.

The Transient Load Tests results for the Thermaltake SP-850M represent the highpoint of today's testing as this unit posts very good overall results and soundly trounces the competition. When directly loaded, the 12v rail showed a peak change of ~310mV and the 5v rail had a peak change of ~80mV when directly loaded while the unloaded 5v peak change during a 12v load was ~90mV. These results have this unit beating the Kingwin PF-850, the Corsair TX850 v2, and the NZXT HALE82 850W. So, this unit is top of the heap among comparable units and that is an extremely nice set of tests results for Thermaltake.

DC Output Quality

In the ripple/noise portion of today's evaluation we see the Thermaltake SP-850M take a rather significant step backwards from the direction it was headed in with the Transient Load Test results. As we see today, the peak 12v trace amplitude was ~40mV while the peak 5v trace was ~30mV and the peak 3.3v trace was ~35mV. That 3.3v value, on a very lightly loaded rail, is right at 70% of the ATX12v specification limit. On top of that, when we compare this unit to the most recent comparable power supplies, we see that this unit can only ever rise to ending mixed with the also poor in this regard Kingwin PF-850 and trails the NZXT HALE82 and Corsair TX850 v2. So, this is certainly not the best by an absolute measure today nor by a relative measure which is unfortunate as the unit really was turning a corner with those Transient Load Test results.


The Thermaltake SP-850M, like a lot of power supplies we see, is supposed to be a quiet power supply (actually according to the back of the box it is "ultra quiet"). Given that the unit has a 140mm overhead fan, really rather good efficiency, and an open layout we do indeed have the stage set for a unit that could be quiet. I also could win the lottery (checks scratch offs) but I didn't and neither did the SP-850M. In short, the Yate Loon ball bearing fan in this unit seems to have been the issue today as the unit was quiet through ~50% of load and then the noise really began to start. When that occurred, we had two distinct things going on. The first was the sound of moving air which was significant, but more annoying was the grinding sound the fan made throughout Test #3, the Torture Test, and Test #4. Even if the grinding noise was eliminated, this unit was still going to be louder than a lot of 850W units we have seen based on the noise from the moving air alone and the fan controller used here could probably use a lot of tweaking to correct that. In the end, this unit is unlikely to make any quiet cooling aficionados happy. For other users, it is going to depend on your usage profile and if you can stay below that 50% load threshold.

Paul's Thoughts:

Today's Thermaltake SP-850M is one of those products you don't see a lot of coverage on since it is kind of pushing into an odd area. At 850 watts it is legitimately a large power supply, but with the feature set and positioning it gets from Thermaltake it is more of a mainstream product where cost will dictate a large portion of its value. In that realm, 850 watts is really starting to push the boundaries of what people will buy making this somewhat of a marginal product that Thermaltake is probably producing because it was easy enough to tack on along with the lower powered SMART series members that this unit shares a platform with. For our purposes though the important part is, does this unit really fill a niche? After reviewing this unit today, looking at the other options out there, and the other things we have reviewed that were similar in the past I am going to say yes it does. People quite often over estimate how much power they need and so when they sort units by power output and then price this unit will pop up near the top of the list ahead of a number of worse options. In that regard, the SP-850M will be a good thing. For more informed users, however, they may find a better lower capacity product for the same price and be better served with that instead. In the end though, this product really does protect people from themselves and that is not a bad thing in this case.

The Bottom Line

The Thermaltake SP-850M passed all of our tests today, but it's performance certainly had its ups and downs. For instance, the SP-850M had literally the best Transient Test results we have seen among comparable 850W power supplies and extremely good efficiency relative to its claims, but then went on to have not-so-good DC Output Quality, back of the pack voltage regulation, and it was noisy. Part of the noise factor was due to the fan controller but also partly due to the lower end Yate Loon fan employed. Thankfully, other than that fan and the few solid Apaq capacitors, the rest of build quality and the support were good for a product that is going to be more of a mainstream offering. So then, how does this stack up against the competition? Well, by performance perhaps not so well but when it comes to price we see that this unit can be had for around $110.99 with Prime Shipping. That price of $110.99 makes this unit actually one of the least expensive 850W power supplies out there from a well known brand that is not real bare bones product, and certainly cheaper than the premium 850W offerings that are not on amazing blow out sale. While price can't do everything for a product, price can make up for a multitude of sins, and today the price argument is going to be a hard one to ignore for this product. Sure it won't be the ideal product for a high end gaming rig, but if you need a good enough 850W power supply that should be a solid performer then the Thermaltake SP-850M fits that value mold to a "T."

Thermaltake Smart Series SP-850M 850W Power Supply