Seasonic has a series of 80Plus Platinum power supplies in capacities of 660W, 760W, 860W and 1000W. The 660W, 760W and 860W models have now been replaced by new versions, so of course we had to test the new versions of these PSUs.
The new models carry the same EAN bar codes as the original ones, but the product code has a two behind it (SS-860XP2 for the new model, where the old was called SS-860XP for example). However, it seems that some online shops are selling the new versions under the old product code, so when you order one of them it's unclear which version you're ordering. Fortunately the original has been end of life for a long time, so you can be 99% sure you're getting the new one when you order the 660W, 760W or 860W model.
Since the arrival of the first Platinum power supplies at the end of 2011 prices have dropped quite a bit, but they're still not cheap with average prices of $146, $172 and $210. If you read our recent review of the Corsair RM Series 750W, you'll know that you can buy a very good 750W 80Plus Gold PSU for less than £100 / €120.
Seasonic manufactures its own power supplies and the Platinum Series also come from the Seasonic factory. Like the previous version, the new models use a single rail design. The three PSUs can supply up to 55A, 63A and 71A on the 12V rails, and that's their entire capacity.
The three PSUs are entirely modular, which they should be at this price point. The motherboard cable is sleeved while the other cables are of the modern flat variety that doesn't require sleeving.
The power supplies have five molex connectors and 10 SATA (nine on the 660W). The 660W and 760W models have four 6/8 pin PEG connectors, the 860W model has six and is therefore suitable for three graphics cards.
The PSUs each have a 12 cm fan and are semi-passive in Hybrid mode. They're not completely silent, as you will see in the noise test.
It's clear that the three new models are based on the same design, as they're almost identical inside.
Seasonic provides seven years of warranty.