We aren't used to reviewing low-efficiency PSUs, especially with extras like RGB lighting, fully modular cabling, and a semi-passive mode. In fact, we think that offering semi-passive functionality on a low-efficiency PSU is more of a marketing trick than a useful feature since high thermal loads won't allow for must passive operation.
As far as performance goes, despite the SPR-0850F-R's not-so-tight load regulation, it offers decent ripple suppression, and the +12V rail's transient response is good as well. On the other hand, the 3.3V rail's performance is disappointing, to say the least. Thankfully it's only lightly used nowadays.
With a price close to $100, the Smart Pro RGB family's strongest member is positioned fairly. We do, however, believe that much of this unit's production cost was devoted to bells and whistles rather than the best performance and reliability possible. We're surprised to see Thermaltake offer a seven-year warranty, given the SPR-0850F-R's low efficiency and Teapo SC caps on the secondary side. The bulk cap may be of good quality (though we'd like to see a larger one with a higher voltage rating), but TT didn't pay as much attention to the caps on the secondary side.
Though RGB lighting may be in vogue right now, we'd rather see higher-quality electrolytic caps that'd age slower, maintaining good ripple performance for as long as possible. After all, when it comes to PSUs, performance matters a lot more than aesthetics. Marketing wins again, it looks like.
Another of the Smart Pro RGB's disadvantage is its single EPS connector, which looks out of place on a 850W unit. Given that most high-end motherboards need two EPS connectors for feeding the CPU, we simply cannot understand why some brands insist on only providing one. More than likely, they do this to prevent competition with their higher-end products. Be that as it may, every PSU with more than 600W of capacity should include a pair of EPS connectors.
All told, the SPR-0850F-R offers good ripple suppression, fully modular cabling, and an impressive seven-year warranty. However, we believe that its efficiency is low for today's standards. In our opinion, it's better to spend a few bucks more for a better power supply.