While Xeon E3-1200 family has been supported since v3.89 according to UMBPCI history, when I tried this on my H97 board with a Xeon E3-1285v4 it complained about my CPU/chipset (8086:1618) is unknown.

This particular ID is actually the CPU's Host Bridge according to this, which is what I got from "dmesg" in a Linux environment as well.

So I opened UMBPCI.SYS with a hex editor and looked for Xeon E3 related stuffs and found the entry for Xeon E3-1200v4, but it was assigned to something called "8086:000b" which certainly isn't right.

To fix this, look for this part in UMBPCI.SYS with a hex editor (v3.90 for example):

86 80 0B 00 00 00 1C 38 01 00 00 00 49 6E 74 65 6C 20 58 45 4F 4E 20 45 33 20 31 32 30 30 76 34 24

You can simply search for text "XEON E3 1200v4" to locate this. The first four bytes needs to be changed, resulting in:

86 80 18 16 00 00 1C 38 01 00 00 00 49 6E 74 65 6C 20 58 45 4F 4E 20 45 33 20 31 32 30 30 76 34 24

And save the modified file. After this modification UMBPCI works on my system and correctly enabled UMB.

Some side notes:
- Xeon E3-1200v3 family (8086:0c08) is correctly supported by UMBPCI.
- Xeon E5 family won't work, because they lack the Shadow RAM functionality needed by UMBPCI.

You can refer to the Volume 2 of the datasheets of those CPU architectures for more info about Shadow RAM. Xeon E3 has those registers (PAM0-PAM6) responsible for controlling the shadow RAM, which are not present in E5.