Unless I'm way off here, the CPU is the key, rather than the motherboard. Check Intel's official page for the processor, and there's an "ECC Memory Supported" (Yes/No) field. Xeons should all support ECC RAM, while the consumer models probably do not.
You are partially right, in the past was like that, but this gen of sandy bridge intel allow their low end pentiums to support ECC with a server chipset. 2nd Generation Intel® Core™, Intel® Pentium® and Intel® Celeron®
Users have also reported i3 2100T, from newegg reviews for the SUPERMICRO MBD-X9SCM-F-O LGA 1155 Intel C204 Micro ATX Intel Xeon E3 Server Motherboard
Pros: Supports ECC even with a desktop CPU (35W i3-2100T in my case), so no Xeon required. Even though it has 8-pin EPS and 24-pin ATX connectors it works fine with 20-pin ATX and 4-pin P4 (e.g. PicoPSU-120).
HP advertise their server with a 2100 with ECC support
. But the i5 n i7 seems they dont have support for ECC.
I would wait for X79/LGA2011 and go with 8x 4gb modules, that way OP gets his desired 32gb of ram and with a desktop chipset and probably a more powerful cpu. If you need ECC, then wait for the new xeon LGA2011.