Eli5 techy: online calculator recommends 400W of power supply, but VGA recommends 650W, is there a problem going below recommended?

341 views

I’m about to upgrade my desktop computer. Using an online calculator and adding my components, it recommends a bit more than 200W of power. When I replace the VGA with the one that I want, it recommends 400W power. But when checking the VGA alone, it’s store page says: power supply 650W or more recommended.

My question is, I already have a 450W power supply, can I go with it? And what happens if the power is not enough? Will I risk any component?

Obs: Perhaps the calculator specifies raw energy, while the power supplies can deliver like 80% of what they say?

In: 1

15 Answers

Anonymous 0 Comments

Good PSUs will report a continuous power rating and a peak power rating. Continuous meaning if you run your computer 24/7 and it regularly uses 435W, you PROBABLY will be perfectly fine with a PSU rated for 450W continuous power output. That being said, some of your pc components, especially a modern GPU might suddenly ask for much more power from the PSU. In this case, you want your PSU to be capable of supplying a peak power output well above the potential power spike your GPU requests. 650W is a good amount for most desktops with a modern GPU. If you have a higher end GPU such as a 3060 or higher, you should consider a 750W or higher wattage PSU just to be safe. Another upside of high wattage PSUs is they’re often more efficient.

TLDR: add at least 20% to the wattage you need, to be safe. Find a PSU that says it can supply that wattage continuously, not just the peak output. Always buy name brand.

You are viewing 1 out of 15 answers, click here to view all answers.