Silver Power SP-S850 PSU

Efficiency comparisons

Compared to other units we've seen (not taking into account voltage quality or subjective noise levels), the Silver Power SP-S850 falls about mid-table overall but it has quite a low 50 percent efficiency compared to others we've tested recently.

The SP-S850 is not only slightly more efficient than the Cooler Master Silent Pro 700W and Enermax Pro 82+ 625W at the same respective proportional load percentage, but it’s also a fraction of the price of both. However let's also remember that the SP-S850 is significantly noisier - especially compared to the Cooler Master.

The BFG ES Series 800W is much more expensive but has sufficiently higher efficiency and is also quieter, whereas the Corsair TX750W is around the same price with the same non-modular cables, albeit 100W lower, and again is slightly quieter than this Silver Power until both reach high loads.

Compared to other 850W units though you'll be usually looking at upwards of £100, so when you shave 20-25 percent off this, it looks like excellent value.

Final Thoughts

So all in all, the Silver Power SP-S850 is a bit of a no frills but essentially solid PSU - it does what it says on the tin and falls around mid table in an efficiency list mostly made up of PSUs that are more expensive and/or lower power. The styling has a quirky retro-esq feel that to some might be a little too plain, but we kind of like the way it tries to be different. Not everyone will want the flashy blue LEDs though and some way to turn these on or off would have been nice.

When you dive a bit deeper though you do find out where Silver Power has made a few decisions that don’t quite cut it in our opinion. It's not the quietest out there, especially as you ramp up the juice and the internal heatsinks, while nice and flashy gold, are not as large as some we've seen - that's part of the reason why the unit needs to get louder than we'd like.

The 12V power provision is a very high percentage of total which is good, but the use of different wire gauges (determining resistance and contributing to efficiency and heat) is inconsistent but not out of line compared to other units. The biggest blunder we see though is the total power division between the four rails and the decision to put the entire PCI-Express graphics on a single 20 Amp rail, yet have two rails for up to two different CPUs is not the best idea: more people will be using multi-GPU instead of multi-CPU these days.

With our PC design hat on, we ask that if you're shelling out for a couple of HD 4870 X2s or a pair GTX 280s in SLI, will you be wanting to top it off with something equally special or just inexpensive to power it all? If you’re not looking at a high end multi-GPU setup, do you really need all 850W, or will simply dropping a power grade and going for something a bit quieter suit instead?

If your mind is made up and you are going to chase the Watts on the cheap, we feel this Silver Power unit should certainly be a consideration, but it's not the definitive choice.

• Efficiency/Voltages
• x
• x
• x
• x
• x
• x
• x
• x
• -
• -
• 8/10

• Noise/Heat
• x
• x
• x
• x
• x
• x
• -
• -
• -
• -
• 6/10

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

• Value
• x
• x
• x
• x
• x
• x
• x
• x
• x
• -
• 9/10

• Overall
• x
• x
• x
• x
• x
• x
• x
• -
• -
• -
• 7/10

What do these scores mean?