Power Supply Reviews
We've been through a lot of power supplies here at The Tech Buyer's Guru, and at any one time we have about six different models running regularly in our bench systems. So from time to time, we'll actually take the time to review some of the models that most impress us!
A few things to keep in mind about our reviews: because we don't have highly-specialized load testing equipment, so we won't be delving into the nuances of voltage stability, hold-up time, quality of each individual rail, etc. Instead, we'll be focusing on what you, the consumer, would most notice: aesthetics, ease of use, noise, and efficiency.
While you can find power supplies ranging in price from $20 or so all the way up to $400 and beyond, we think that most users will be best off looking in the $50 to $150 range, with budget buyers sticking to ~$40, and ultra-high-end users looking at some of the more "elite" power supplies in the $200 and up range. One feature we really recommend if you can afford it is fully-modular cables, which is a fancy term for removable cables. These make the final product a whole lot neater, and sometimes make inserting the power supply easier as well, although they do require at least basic knowledge of which cables you'll actually need to attach and which can be left in the box.
We also think that at this point, most high-end buyers should be looking at something more efficient than the basic 80 Plus or 80 Plus Bronze power supplies. These ratings refer to the efficiency at 50% load, and 80 Plus is 80% efficient, while 80 Plus Bronze is 85% efficient. There was once a big market for 80 Plus Silver (88% efficient) models, but the high-end market is now dominated by Gold (90% efficient) and Platinum (92% efficient) power supplies, with Titanium (94% efficient) units available in the extreme price bracket. While all 80 Plus-rated PSUs must meet 20%, 50%, and 100% load efficiency targets, only Titanium has a target for 10%, which is where a lot of PCs are likely operating. Its 10% target is an impressive 90% efficiency level.
Note that at idle, or even during moderate use, many power supplies will be significantly less efficient than their rating, as efficiency is essentially a bell curve, and 50% load is always the point where you see optimum efficiency. So, for example, a 500W unit with a basic 80 Plus rating, powering a system that requires just 50W in moderate use, will be extremely inefficient. It's operating at just 10% capacity, where it's like turning just 70% of electricity into usable power, and the rest into heat (and thus fan noise). This is why we always recommend users think carefully about their usage scenarios and not "overbuy" when it comes to wattage. For an office PC, choosing a high-efficiency 450W power supply will be a whole lot better than choosing a low-efficiency 1000W power supply! Alas, for various reasons, you won't find ultra-low wattage, high-quality power supplies, even though PCs are now so efficient that a gaming PC can use just 250W at peak load, with most office PCs using just 100W at peak load. Hopefully manufacturers will one day market excellent 250W units, but until that day comes, we'll all be stuck over-equipping many of our PCs!