Best Video Card For 300w Power Supply

Choosing the best video card for your computer is not always easy, especially if you have brand name desktop with a very limited power supply. Personally I never recommend such computers to anyone, because usually there aren't a lot of upgrade options available.

In computers made for home or office use there's no need for serious video cards, so manufacturers choose to install 200-300 Watt power supplies, which barely cover the power requirements of the best processor you can upgrade to. This is why it's better to build your own computer with parts that will support future upgrades, at least in the next 3-5 years.

This is the specification sheet of an average 300W power supply. As you can see the total maximum power of 300W cannot be delivered to just any component on any circuit, because there are very strict rules, which protect the physical integrity of the power supply and components. Although engineers have worked a lot on the design of the computer's switching power supply, they haven't been able to come up with a very flexible solution at an acceptable price. This is why we have today very cheap power supplies, some with crippling limitations (ex: can be burnt by a simple Core 2 Duo processor), while others cost a bit more and offer about 400Watts of power for reasonably high-end hardware components.

In theory any 300W power supply will support a video card that doesn't need extra power cables, but there may be some CPU + video card combinations that simply overload the power circuits. For example a quad core Phenom II X4 processor that requires 125Watts and an AMD Radeon 6670 video card need about 190W together (even more if overclocked), so if the other components of the computer exceed 110W, then the power supply is compromised.

Some careful settings may be required if you're determined to install the best possible video card in a lower high-end Intel computer, as the latest few generation of processors sometimes use a lot more power than they officially need. Personally I have been able to configure my LGA1155 motherboard and the Celeron G530 dual core processor to use up to 84Watts of power (sustained), but a Core i5 processor that supports TurboBoost can draw up to 150Watts short term (for just a few seconds). Depending on the motherboard type, such a computer configuration (with any kind of video card) will either overload the 300W power supply or simply slow down the processor in order to stay within acceptable power limits.

My recommendation is to not install video cards in computers with a 300W power supply, or choose a low-end card.

Watch tweets on: