"Yes, SketchUp can take advantage of hardware acceleration.
In SketchUp navigate to the Window menu. Click Preferences -> OpenGL Check Use hardware acceleration and hit OK.
A better video card will definitely improve performance. SketchUp is highly dependent on GPU power. From the words of Google:
We recommend any graphics card that fully supports OpenGL 1.5 or higher and has at least 64 MB of video memory. If you're going to create large models, we recommend a graphics card with more than 64 MB of video memory.
For more information see Which graphics cards are recommended for SketchUp?"