Xenon The first motherboard and probably the best for JTAG'ing online is the XENON motherboard. It was released with the xbox in November 2005, it does not have a HDMI port so you cannot play in HD. The Xenon motherboard was a standard stock motherboard from November 2005 to July 2007. Zephyr Zephyr is the second motherboard bought in to all newly made consoles after July 2007. Although microsoft was aware of the Red ring of death, they released this without fixing it, so it is possible to get the RROD with your zephyr motherboard. Falcon The Falcon motherboard for 360 was released just one month after the Zephyr, in September of 2007, because of the zephyr's Red ring of death problem, the Falcon's power supply was slightly reduced. The slightly reduced power supply ended up not being the fix for the RROD problem. Opus The Opus motherboard for the xbox 360 was released in June of 2008. The opus was a modified version of the Falcon and was released for the returned Xenon consoles which has Red ring of death hardware issue. Which they replaced the motherboard to an Opus. The Opus did not come with HDMI and was only used for Xenon repairs. Because of Microsoft replacing the motherboards instead of replacing the consoles, this saved Microsoft Millions. Jasper Jasper was released in September of 2008 and was the first hit on the head for the RROD hardware issue. Microsoft replaced the cooler to a smaller version and having a more reliable GPU because of the smaller cooler the Jasper fitted consoles were alot quieter than the rest of the motherboards. ValHalla All information of previous motherboards has come from my own knowledge or other sources, Valhalla is the newest motherboard although the specifications are unknown (to me). Which motherboard do you have without opening the console? The easiest way to find which motherboard is to look at your xbox 360's power connector on the back of your 360.