Looking for the best video card I can get for under $300

[CrossStealth]

Hello its bee a while since Ive been here. About a year or so since I built my pc. My girlfriend just got my dads pc that he built and she would like to up the video card in it and has about 300 to spare. I haven't been looking at the newer video cards that have come out. She is an artist and uses very very demanding software and has to run multiple applications so she needs no lag while doing this. She has 4gigs of DDR2 ram so hopefully that will help. Its in windows 7 64bit by the way.

Her motherboard is GIGABYTE GA-G31M-ES2L
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128357&cm_re=ga-g31m-es2l-_-13-128-357-_-Product

her processor is an Intel Pentium E5200
http://www.newegg.com/Product/Product.aspx?Item=N82E16819116072&cm_re=E5200-_-19-116-072-_-Product

Her current Video card is an Gigabyte Radeon HD 4350 512MB
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125251&Tpk=HD%204350

Oh and if it matters she has 2 2gb sticks of CORSAIR XMS2 2GB
http://www.newegg.com/Product/Product.aspx?Item=N82E16820145201

I know its not the best equipment but in your expert opinions what would be the best way to go with a new video card?

Random side question I am currently using vista 64 on my computer and its rating on ram is 5.8 not 5.9. I have 8gb
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231219 and http://www.newegg.com/Product/Product.aspx?Item=N82E16820231209

2 of each stick. Why dont I have a perfect 5.8?

Thanks in advance

 

[jaguarskx]

Power Color HD 5850 => $290 shipped

http://www.newegg.com/Product/Product.aspx?Item=N82E16814131184&cm_re=hd_5850-_-14-131-184-_-Product

 

[CrossStealth]

Power Color HD 5850 => $290 shipped

http://www.newegg.com/Product/Product.aspx?Item=N82E16814131184&cm_re=hd_5850-_-14-131-184-_-Product

Thats the one I have been looking at. Seems to be the next best thing after the GTX 295 at a cheaper price. The only better card ive been able to find is the HD 5870 which seems to be out of her price range
Thank you

 

[sabot00]

I doubt artist software is heavy on the GPU, at least not the the extent that a 5850 would make much difference over say a 5670.
Upgrading the CPU might have a bigger impact if the E5200 is stock.

 

[CrossStealth]

I doubt artist software is heavy on the GPU, at least not the the extent that a 5850 would make much difference over say a 5670.
Upgrading the CPU might have a bigger impact if the E5200 is stock.

I can agree that the cpu would have a bigger impact but I put one of her programs on my pc and using her biggest brush I still saw significant lag and I am running a GTX 285 8gb of ddr2 ram and have a intel core 2 quad Q9550 500gb HD. Stuff I would consider high end. Not sure how high end they are anymore though.