Differentiating the Quadro FX 4600 and Quadro FX 5600 is the amount of memory. The lower Quadro FX 4600 features 768MB of video memory – similar to NVIDIA’s GeForce 8800GTX. A whopping 1.5 GB of video memory is available on the Quadro FX 5600; besting ATI’s 1GB of graphics memory endowed FireGL V7350. Both Quadros have 384-bit memory interfaces though.
If you are a hardcore 3D designer and want the best, the top-end FX 5600 will only set you back a smooth $2,999. Don’t fret though. The slightly feature reduced FX 4600 costs only $1,995.
Source: Daily Tech