The 2.2 spec assigns the Capability ID of 02h to AGP. The remainder of this section is only included as an example of a New Capability.
Refer to Figure 22-25 on page 845.
The AGP's Capability ID is 02h.
The second byte is the register that points to the register set associated with the next New Capability (if there is one).
Following the pointer register are two, 4-bit read-only fields designating the major and minor rev of the AGP spec that the AGP device is built to (at the time of this writing, the major rev is 2h and the minor is 0h).
The last byte of the first dword is reserved and must return zero when read.
The next two dwords contain the AGP device's AGP Status and AGP Command registers.