dedicated video card question

I'm currently using integrated Intel g45 chip on the motherboard as my primary video processor with shared 128mb memory.
It's pretty quick and fast, no problems, whatsoever.

However,

Will I get major boost in Lightroom or Photoshop if I buy a dedicated video card, like nVidia GT 440 128bit ddr3 1gb ram?

I don't do 3D, ever, just photographs & vectors. I have Intel Duo 84000 cpu with 4GB ram, 64bit win7.

Thanks.
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