CHOOSING YOUR PSU
HOW MUCH POWER DO YOU NEED?
RATED POWER
Enough power for your system.
EFFICIENCY RATING
A higher rating means lower electrical bills.
NOISE LEVEL
A good fan makes all the difference.
Your CPU and graphics card demand far more power than any other component.
Luckily, their peak power draw is one of their main listed specifications.
1) Search for your GPU model's TDP or power draw online. Try to find the specific card manufacturer version, since some cards with the same chip are tuned to consume more power than others.
2) Do the same for your CPU.
3) Now add 150W for the combined power usage of your motherboard, fans, memory, storage, and peripherals.
4) PSUs don't operate at their highest efficiency when at full load, and you may want to add more headroom for future upgrades. We recommend adding 150W of headroom to what you have so far.
Add the numbers up, and you now have the PSU power to aim for when choosing your PSU.
Or, if you don't want to do the math, leave the calculations to the CORSAIR PC Builder, which includes all the relevant TDP figures in its wide-ranging database.
EFFICIENCY RATINGS MATTER
Efficiency ratings on PSUs indicate whether the PSU has been tested to meet the requirements of the 80 PLUS standard. In short, efficiency is the measure of how much power your PSU can direct to components, and how much is converted into heat.
The efficiency of most PSUs varies between about 80% and 96%. Efficiency varies with load, and primarily depends on the quality of transistors, capacitors, and other components used in the power supply unit.
This means that a power supply rated at 80% efficiency is able to provide 80% of the power it draws from the outlet to your PC components, and the remaining 20% is turned into heat.
First of all, any electricity that ends up as heat is wasted, which shows up in your electric bill. The PSU is going to have to cool itself more as well, and that is going to show as increased PSU fan noise.
Therefore, when choosing a PSU, you should consider the efficiency of the unit as it affects power consumption and noise during long gaming sessions.
THE FORGOTTEN SOURCE OF PC NOISE
Power supplies also impact the noise of your PC. A PSU operating close to its maximum rated output will need to ramp up the fan to stay cool.
ZERO RPM FAMILIESAXiHXiRMx
Most power supplies can ramp up their fan when needed, and some feature "Zero RPM mode". If system noise is important to you, your power supply unit should be able to operate without a fan during most non-intensive loads, and with minimal fan speed during gaming system loads. In addition to Zero RPM Mode, you can achieve this by selecting a PSU with:
- High efficiency rating (less heat to remove)
- Extra headroom in the listed wattage (keeping it from operating at maximum load)
If all of this is starting to get a bit too complex, you can also rely on our PC Builder to recommend a PSU based on your other components.
PSU BUILDERS GUIDE
Learn about sizes, form factors, modular cables, and other questions that influence your build experience.
