Verdict: Akasa goes retro with this all-new twin12V-rail PSU.
We haven't tested an Akasa PSU in some time, as the company has been focusing its attention on the low-wattage end of the market. However, Akasa has just launched a new range of high-end PSUs called PowerMax, available as either 850W or 1kW models.
The PowerMax adopts a very different approach from most high-wattage PSUs, which split their load over several (typically four to six) 12V rails. This approach means that power-hungry components such as the CPU and graphics cards will each have their own separate power source, which is a more logical way of distributing this much power. However, multiple 12V rail PSUs are complex, and therefore expensive to design. Akasa uses just two 12V rails in the PowerMax.
Each of these 12V rails is rated as being capable of supplying up to 35A, and they distribute their load as follows: 12V1 powers the motherboard, half of the CPU, two of the PCI-E cables and the Molex ports, while 12V2 powers the other half of the CPU, the other two PCI-E cables and the S-ATA ports.
Despite its retro design, the PowerMax was perfectly capable of outputting its full 768W from its two 12V rails without a hitch. It also proved to be one of the most efficient PSUs we've tested, averaging 85 per cent at full load, needing only 999W to generate 850W.
The downside of this is that all the cables are hard-wired into the PowerMax, making it harder to build a neat and tidy PC than it would be with a modular PSU. The fan, while not particularly loud, could also be a little quieter in an ideal world.
Conclusion
Although the PowerMax eschews conventional wisdom and places all its 12V power in the hands of just two rails, it's a good PSU. It's not particularly loud, it's extremely efficient and has plenty of power to spare for multiple graphics cards, plus a heavily overclocked quad-core CPU.
However, as good as this PSU is, you'd always choose the Antec Quattro 850, which is quieter, costs roughly the same, has modular cables and is nearly as efficient.
