Beta
History
Beta hardware came in two flavors; internal kits, and eventually development kits. As previously noted the nomenclature of "Beta 1" and "Beta 2" was created by the scene and not accurate, but commonly known. A more accurate way to identify beta hardware is by board revisions. You can find the revision string behind the ROL, it will say X801054-005 through 008 or X803600-009 through 010.
Internal units will be in a white case with stress wires. Known board revisions that came as internal units are 005-008. It wasn't until board version 007 when Microsoft made a full development unit to send to developers. That unit is the only beta development kit referred to as Xenon Development kit (XeDK) on the mfr (no mold branding on case). Board revisions 008 - 010 are given final branding of "Xbox 360" on MFR and case.
Beta development hardware were later replaced with final Xenon XDKs. Microsoft required that studios return their Beta units after their use had ended. They were intentionally damaged by Microsoft before and then shipped overseas with the intention of being destroyed.
Chinese sellers on marketplaces such as TaoBao began selling the damaged Beta units which is where the term "China Kit" originated from. These kits often came with destroyed AV/ethernet ports, missing sidecars and also had their serial numbers defaced with a disc grinder. With the ports being identical to the launch model Xenon, the damage was relatively easy to repair and were obtained by many different community members.
Board revisions 007 and below are restricted to pre-release software, making them more of a collectors piece then a useful unit. Board revisions 008 and above are capable of going to latest recovery, making them more useful for enthusiasts.
In order to prevent confusion between users, using the PCB part number of an XeDK is usually preferred over using the Beta 1/2 moniker.
Beta 1 (Revs 001-008)
Unlike board revisions 008 and 009, board revisions 005-007 feature a Titan debugging board. 005-007 board revisions also use an earlier XCPU that was clocked at 2.8GHz instead of the final 3.2GHz clock speed. As a result, they are only able to run XEX1 applications and are not able to run retail or retail patched games. 008 an onward use final 3.2Ghz clocked XCPU
All Microsoft custom chips in 005-007 are labelled as engineering samples. It is believed that there is little (if any) difference between the Beta 1 GPU, Southbridge, ANA chip and their retail counterparts.
Revisions 005-007 can not run recoveries later than 1838.1.
Internal kits
As Mentioned above Internal kits are white kits with stress wires. They also might have there Argons programming wires sticking out aswell. They were used for internal hardware stress, configuration and software programming. We haven't seen any internal kits of board revisions 009. Known board revisions as internal kits:
005
Very early console and parts. Case is a glossy white. Titan board is rev 00.80
007
these are not known as XeDK! they are just 007 internal kits, not development kits.
Titan board version earlier then titan board in the XeDK units. Common titan board revision seen to be Ver 1.7. Seen with and without inverted Argons.