Example at http://www.tomshardware.com/forum/367004-33-gt610-graphics-card
But the answer is no. Changing the power supply will not improve the GPU.
Just wondering, why not the slightly better GPU I recommend for such machines? That's the ATI 5450 1GB card.
Bob
i have a gateway sx2802-03 with a nvidia gt610 installed. the PSU is 220w but the graphics card says it needs a minimum of 300w. ive been using it for a few months now with the 220w. I wanted to know if running it underpower was alright and if i upgraded the psu to a 400w or so if that would improve my GPU preformance.
here is a link to the PSU from what i found

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