Built Not Bought
Computers can be an expensive bit of equipment to buy and you want to get the best computer you can for your budget. You've decided on the main components of the PC a good Processor that will allow you to run your games and stream them to the interwebs at the same time. Enough Memory that runs at the perfect speed to match your workload. And a Graphics Card that will manage the buttery smoothness of 1440p resolution with 144Hz refresh rate. You put all of these expensive components in a sleek looking Case with tempered glass and enough RGB lighting to create your own mini disco.
But after checking your budget you only have a small amount left for a Power Supply. Scouring that well known next day delivery website you stumble across a couple of potential options that meet your budget. The Power Supply calculator told you that 500 Watts is enough to power your system and you have narrowed your search down to one particular unit. 600 Watts and it's only £15! Awesome!...Right?
There are a number of things that should be checked before you make choice here. First off does the power supply have any safety features and protections such as Over Voltage Protection or even Under Voltage Protection. There are many more safety features that are standard in a lot of power supplies that you won't find in these cheaper units. Such as Over Current Protection, Over Power Protection, Over Temperature Protection and Short Circuit Protection.
The next thing we should look as is the efficiency rating, most decent modern power supplies now are rated with an "80+" certification. This ranges from 80+ also called 80+ White, 80+ Bronze, Silver, Gold, Platinum and Titanium being the most efficient at 94% efficient with 100% load. The more efficient your Power Supply is the more power it will be able to output with less waste and it will also draw less power from the wall and therefore cost less to run.
If we take a look at this 400 Watt BeQuiet! Power Supply, we can see it is 80+ Bronze rated and has a max combined output of 32 Amps or 384 Watts on the 12v rails or 96% of the total combined power. We can check this with a simple equation...32 Amps x 12 Volts = 384 Watts
Compared to this unit that will remain nameless we can see the 12v rail on the 500w unit is only rated at 18 Amps. If we do the same calculation 18 Amps x 12 Volts = ONLY 216 Watts! That is less than half of the total power only 43%!
Computers are very sensitive pieces of equipment and when a cheap Power Supply fails it could send a surge through the components in your system. This can harm the components and stop them from working correctly or even stop them from working at all.
Get a good branded power supply, a one that has good protections and is at least 80+ rated, check the specifications and see how many Watts the 12v rail has available. Remember the easy calculation is Amps x Volts = Watts. Cheap power supplies like the one shown above can be useful in some situations like for example a home or office PC just used for browsing the internet or doing office work. These type of systems tend to have integrated graphics so a relatively low powered systems.