Supported System Software: 7.1.2, 7.5, 7.5.1, 7.5.3
SCSI: DB-25
Serial Ports: 2
Sound Output: stereo 16 bit.
ADB: 1
Ethernet: AAUI-15 built-in
Machine Gestalt ID: 112

Minutiae:

Upgraded with two SIMMs at a time.

Can be accelerated with Newer Technology's  256KB Cache SIMMs,  part # 7CC256A.

Can be accelerated with Newer Technology's Eddy Award winning "PowerClip™", part # 7MC601.  The PowerClip has over 100 different speed settings. The PowerMac 7100/66 can be set at speeds of up to 84MHz. Typically the 7100/66 will be set to something between 76MHz and 82MHz.  The PowerClip is slotless and therefore leaves all expansion slots open.

Original enabler: Power PC enabler v1.0

Serial Port with the phone icon supports synchronous modems, with handshaking on both the output and input.

Has 4MB ROM and a 1.44MB SuperDrive.