I'll do a low down for you.
These are the xbox360 motherboards:
1st Gen:
Xenon - 90nm CPU + GPU - Launch model (prone to 3rod)
Zephyr - 90nm CPU + GPU - Revised Xenon model (still prone to 3rod)
2nd Gen:
Falcon - 65nm CPU + 90nm GPU - Included HDMI port (prone to E74 and 3rod)
Opus - 65nm CPU + 90nm GPU - Xenons send in for repairs, were replaced by Opus motherboards but these were without HDMI ports. (prone to 3rod)
3rd Gen:
Jasper - 65nm CPU + GPU (no large scale confirmed reports of error yet, best bet to get)
Now for the Bundles:
Arcade - Console + Controller + 256/512MB memory card + SD cables + 5 Arcade titles disc
Go Pro - Console + Controller + 20/60GB HDD + Ethernet Cable + LIVE headset + HD/SD cables
Elite (all accessories in black)- Console + Controller + 120GB HDD + Ethernet Cable + LIVE headset + HDMI cables + HD/SD cables
yes, it took me a while to write this down. So some gratitude would be nice.