Cube and 23" HD Cinema DIsplay

I have a G4 450 Cube running 10.4 which is essentially stock spec save for some extra ram (832mb). I've recently been offered a decent deal on a 23" HD Cinema Display (the one with the plastic case that matches the cube) and I know enough to know that I need a new video card (but that's pretty much where what I know ends).

I've extensively searched both this forum and others (not nearly as helpful) but must admit that I am still quite confused. My technical skills are limited and while I'm willing to swap faceplates and install the card, that's where what Im willing to do ends. Any more "advanced" modding is over my head.

I was pretty much set on buying either a GeForce2 MX Twin View 64MB ADC/VGA (apple part # 661-2508) or the nVidia GeForce II MX for Mac G4/Cube (apple part # 661-2408). I was under the impression that all I needed to do was swap the faceplates and install but recent searches of this forum have indicated that I may have a heat dispersion problem so now I'm confused again.

I would be forever indebted if someone here could please tell me if I could use either of these cards in my cube without addind a fan or changing the heat sink. If not, is such a card available or should I not bother buying the monitor.

Thanks in advance for your help