600 - 700W PSU Review Round-Up

SilverStone OP650 650W

Manufacturer: Silverstone
UK Price (as Reviewed): £81.84 (inc. VAT)
US Price (as Reviewed): $89.99 (ex. Tax)

With a retail price of just over £80 and rated at 650W, the SilverStone OP650 resides roughly in the middle of this PSU round-up.

It has a single 12V rail as opposed to two or four. This is rated at up to 54A, the joint highest for a single 12V rail on test, which bodes well for power efficiency. Unfortunately, it has captive rather than modular cables, which is something of a surprise at this price point.

The OP650 maintained voltages within the ATX specification from all its rails at 50 per cent load. However, during the stress test, the output from the 5VSB rail slipped to 4.72V. With the ATX spec requiring a minimum of 4.75V, this counts as a fail, although it’s the only fly in the ointment for this PSU.

The OP650 has a single 8-pin PCI-E connector and a further four 6-pin PCI-E connectors, which means that it can’t support more than one high-end graphics card without the use of adaptors. There are six SATA and six Molex connectors, which should be enough for most systems, even one with lots of fans, drives and lights.

The 120mm fan was quiet up to 50 per cent load, and only became noisy at full load. Even so, it was quieter than many of the other PSUs in this Labs test, and it’s unlikely that you’ll draw 650W from it for long periods of time. At 50 per cent and under full load, the OP650 was 86 per cent efficient, which is pretty good, although several other PSUs were an amazing 89 per cent and even 90 per cent efficient. The OP650 is the best PSU we’ve seen from SilverStone for a long time. However, it isn’t the slightly weak 5VSB rail that lets it down, but the fact that, at this price, it has captive cables. For a little less money, you can pick up the Antec TruePower New TP-650, which has flawless stability, a quieter fan and modular cables.

• Stability
• x
• x
• x
• x
• x
• x
• x
• x
• x
• -
• 9/10

• Features
• x
• x
• x
• x
• x
• x
• x
• -
• -
• -
• 7/10

• Value
• x
• x
• x
• x
• x
• x
• x
• -
• -
• -
• 7/10

• Overall
• x
• x
• x
• x
• x
• x
• x
• x
• -
• -
• 8/10

Score Guide

Akasa Eco-Friendly Power 600W

Manufacturer: Akasa
UK Price (as Reviewed): £63.38 (inc. VAT)
US Price (as Reviewed): N/A

The Eco-Friendly Power 600W is certainly cheap; only the SilverPower SP-SS650 and ghastly generic PSU are cheaper.

Unfortunately, if there’s anything cheerful about the Eco-Friendly Power 600W, it doesn’t manifest itself in the cables, as these are captive, not modular as we prefer. There are two 12V rails, each rated at 30A, but they can only supply a combined total of 41.6A, which is a little on the low side compared with the other PSUs on test.

Akasa has configured 12V1 to supply the motherboard and half of the ATX12V connector, as well as the disk drives. Meanwhile, 12V2 looks after the other half of the ATX12V connector and also the PCI-E connectors, of which there are two 6+2-pin and two 6-pin. The Eco-Friendly Power 600W also has six Molex and six SATA connectors. Like a lot of brands, Akasa doesn’t manufacture its own PSUs; the Eco-Friendly Power 600W is made by Enhance.

The Eco-Friendly Power 600W passed the Chroma’s barrage of tests, although 12V2 was on the weak side and drooped very close to the 11.4V minimum limit of the ATX specification. In a wobbly moment, 12V2 dropped to 11.52V in our stress test, which is low but still a pass. The Eco-Friendly Power 600W will be very cost-effective to run – at 50 per cent load, it was 88 per cent efficient, although its efficiency dropped to 85 per cent during our full-load stress test. The fan was quiet throughout testing, although we noticed a distinctive whiff of something unpleasant from the PSU towards the end of the stress test.

The Eco-Friendly Power 600W is stable, quiet and efficient, and better in all respects than a generic PSU. However, it doesn’t compare well with other banded PSUs such as the Antec TruePower New TP-650, which has modular cables, 50W more power on tap and costs just £10 more. In our view, this £10 is definitely worth paying.

• Stability
• x
• x
• x
• x
• x
• x
• x
• x
• x
• x
• 10/10

• Features
• x
• x
• x
• x
• x
• x
• -
• -
• -
• -
• 6/10

• Value
• x
• x
• x
• x
• x
• x
• x
• x
• -
• -
• 8/10

• Overall
• x
• x
• x
• x
• x
• x
• x
• x
• -
• -
• 8/10

Score Guide