• MiTAC/Trigon Darwin 2.3
• Sun A21
• Sun A22

• Expansion slots are on proprietary riser

The listed slots are on the riser card that came with the motherboard.
If you have this board make sure you have the riser for it.

Note on CPU and Firmware Compatibility

The Sun Ultra 10 motherboard (375-0009) is tightly coupled with specific CPU module types and OpenBoot PROM (OBP) firmware revisions. It is not compatible with all UltraSPARC-IIi processor cards:

• Boards originally shipped with Sabre processor modules (e.g., 501-4379, 512KB L2 cache).
• The fastest supported Sabre CPU on this board is the 360 MHz 2MB cache 501-5222 module.
• Sapphire Red UltraSPARC-IIi CPUs (250nm, 2MB cache) such as the 501-5149 440 MHz module can function, but only on higher-quality 375-0009 boards and only with OBP version 3.19v4 or later.
• Earlier OBP revisions lack the necessary microcode support for 250nm Sapphire Red CPUs.

Sapphire CPUs are not drop-in compatible with Sabre-only boards/cards.

Memory Compatibility Notes: The Ultra 10 uses 168-pin 3.3 V ECC Buffered EDO DIMMs. The memory controller resides in the UltraSPARC-IIi CPU module and requires:

• DRAMs with 8K refresh addressing - modules using 4K-refresh DRAMs will be detected at half capacity or less.
• DIMMs with 11-bit column addressing (64 MB, 128 MB, 256 MB modules); older 16 MB DIMMs with 10-bit columns are not compatible in mixed configurations.
• All DRAM accesses are ECC-protected; 64-bit data + 8-bit ECC (72-bit DIMMs).
• Up to four DIMM slots are provided in two memory groups (Group 0 and Group 1), each handling two DIMMs.

Memory is interleaved and accessed as 64-byte cache lines. Non-cacheable memory access is not supported.

For more detailed RAM analysis and upgrade considerations, see: Sun Ultra 5 / Ultra 10 RAM (memory upgrade notes)

Expansion and Riser Slot:

• The Ultra 10 uses a DARWIN SEALION PCI riser card, providing four 32-bit PCI slots.
• The riser connects via a 32-bit proprietary Sun PCI riser connector (not standard ATX).
• For the riser pinout, see Service Manual section C.1.5.2.