This question already has an answer here:

I am planning to upgrade my computer case- A new graphic card and RAM to 16 GB.

PC Config : Processor : Intel Core i3 2nd Gen
Motherboard : Intel Desktop board DH61WW
RAM: 4GB (upgrading to 16GB)
Graphic Card : ZOTAC NVIDIA GeForce GT 630 Synergy Edition 4 GB DDR3 (New)
Tv Tuner Card : 1 Aver Media Super 009 (Internal)

Do i have go for a PSU with more than 450 W ?

marked as duplicate by nerdwaller, Ƭᴇcʜιᴇ007, Dennis, ChrisF, TFM Mar 17 '13 at 15:41

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.


With the data you supplied (and I added 2 7200rpm drives and 2 of your vid cards) you shoould be good with your 450 watt PSU.

If your system grows, you are nearing the limit and you may need to upgrade if you add more items. This was figured with PSU calc newegg and you can add or remove comonents to see what the Watts needed will be.

psu results


RAM sticks only use a few Watt each. You can usually ignore the RAM when deciding on a PSU.

This is not true for most graphics cards. A modern graphics card can use up to 225 Watt. (That is the max specified for cards complying to the PCIe standard). Most of that is drawn in the form of +12 volt.


  • Check how much power your potential future graphics card will use.
  • Check if you PSU is up to the task (for a mid sized card a 450 Watt PSU usually is more than enough).
  • If you see any text stating "needs an XXX Watt PSU" then laugh and ignore it. What they usually mean is 1) This card need 150 Watt from +12, 2) most 450 Watt PSU can deliver up to 200 Watt on the +12 volt rails, 3) lets claim you need a 450 Watt PSU. Which is not always true.
  • Also not always perfectly correct, but a good starting point are power calculators such as http://www.extreme.outervision.com/psucalculatorlite.jsp and http://www.thermaltake.outervision.com/.

Here you go, I use this myself:

Power Supply Calculator

Not the answer you're looking for? Browse other questions tagged or ask your own question.