Do I need a new power supply if I add this graphics card?

[ArtKix]

I have a HP Envy 750-116.
http://support.hp.com/lt-en/document/c04803066

Its power supply is 300w. I've added another HDD (6 watts)

I have an ASUS HD 6670 (1 gig ram, Radeon) card handy which is supposed to have low power consumption. Would I need a new power supply if I use this? If so, how much? 450w?

 

[Suzuki@1473780084@1473780163]

what graphics card did you have in mind? yes, thast likely a crap power supply. obviously powering a hd 6670, but if you bought it prebuilt, then thats literally all its designed to handle. watt is actually not really important, when choosing a graphics card, make sure its of good quality (high quality components), and a +12v amp value that is high enough for a more powerful graphics card.