There is no point in buying a PSU with way more potential power than you’ll ever use. A PSU calculator web page or software can be handy in finding a rough estimation of the wattage requirement of your build. However, it is not recommended to purchase a PSU just above your system’s power needs. A PSU delivers maximum efficiency with a 40 to 60 percent load. Besides, the performance of a PSU declines with time. So, you better opt for a PSU capable of taking you through your next few upgrades for multiple years. You must buy a PSU that fits inside your PC case. Higher-wattage PSUs tend to be a bit longer to house the additional power components they need. This may create issues with cable routing or even with placing other internal components inside the case. The Value Top VT-S300 Real 300W Output Power Supply comes with 1 Year Of Warranty. Specification Matured and stable circuit design High precision components with the most reliability High specification pure copper filter coil to ensure the output voltage is more stable Dedicated power-saving chip-set Quality verified Fully compatible with SATA interface HDD Special control chip-set with multiple protection Silent fan with the best cooling Support AMD and Intel processor Continuous Power: 200 Watt Voltage: 100-240 VAC Modular Type: ATX 12V 2.4 Total Power: 300W AC Input: 100V-240VAC DC Output: 300W Main Power: 1 x MB 24(20+4) Pin CPU: 1 x 8(4+4) Pin EPS 12V 1 Years warranty