I think the best solution for your problem is to buy a HDMI to DVI cable, witch you could also use on your PS3.
The sound problem is easily solved, but requires a little trick, since you can get the image from the HDMI cable, and the sound from te AV connection with your old Component cable.(you can connect two cables at the same time).
The thing is that Microsoft put the HDMI out connection close to the AV cable connection on purpose, so that you think you have to buy their $50 cable that you can only use on their system.
Now the trick: Take your old component cable and carefully remove te lower side of the plastic casing around te connection. This leaves a flat metal surface, witch takes up less space. Now it fits perfectly with any HDMI cable! I use this solution to and it's great.







