Usb frame grabber/ game capture card for playing with a laptop

Hi all,

Sorry if this has been asked before, I have tried searching and the threads I have found are all pretty old (from 08-09) so doesn't apply for today's hardware...

Basically want to know whether I will be able to use a game capture card to play the PS3/xbox games on my laptop display.

I used to do this with my PS2 back in 2005, but from what I have read, the bandwidth of HD signals is too high to carry over usb 2 without significant lag... is this true? if not, which is the card to get?

Please don't recommend me getting a HDTV, i know this is easier, but I am living in a hole right now and moving around every couple of months, so its easier to stay super portable and be able to get my worldly possessions out of wherever I am with 1 trip to the car..!