hd 5670 will be absolute perfect for you it has the latest dx 11 support and also is ati's one of the famous card for budget games and will work perfectly for your 3D rendering and other applications too..
talking about power supply it will run fine on your 360watt psu
Hmmm... It would appear that on NewEgg, they are suggesting a minimum 400 Watt power supply for this item: http://www.newegg.com/Product/Product.aspx?Item=N82E168... If i dont have that much voltage coming from my computer, what will happen? how will it affect the Video Card and the System it's self?