My mobo is IPISB-CU it has an x16 slot (which i thank is 2.0) the 660 is a 2 slot video card. (it looks like it want fit but i dont know.)
here's a screen shot of the mobo itself.
http://h10025.www1.hp.com/ewfrf/wc/document?cc=us&lc=en&dlc=en&docname=c02980014
here's a screen shot of the mobo itself.
http://h10025.www1.hp.com/ewfrf/wc/document?cc=us&lc=en&dlc=en&docname=c02980014