Kingston ValueRAM 16GB 240-Pin DDR3 SDRAM ECC Registered DDR3 1600 Server Memory (Intel Validated ) Model KVR16R11D4/16I

Pros: 16GB per module
4-Channel ECC memory
8.5 Windows Experience Index score

Cons: Operates as DDR3 1333 with lower end Xeon processors
Latency could be lower (but that could cause higher error rates)

Other Thoughts: Just to correct my previous review: this memory achieves a 8.5 Windows Experience Index.

Some additional benchmarks collected with Aida64:
Read: 15,831 MB/s
Write: 13,893 MB/s
Copy: 16,674 MB/s
Latency: 59.8 ns

System:
CPU Type: 8x Core Intel Xeon E5-2690 (Sandy Bridge-EP)
CPU Platform / Stepping: LGA2011 DP / C2
CPU Clock: 3445.9 MHz (SpeedStep overclock: 19%)
Chipset: Patsburg C600/X79, Intel Sandy Bridge-EP

Pros: 16GB per module
4-Channel ECC memory
8.1 Windows Experience Index score

Cons: Operates as DDR3 1333 with lower end Xeon processors

Other Thoughts: Upgraded a Dell T7600 workstation with one of these. With a Xeon E5 2.1 GHz processor, the speed topped out at DDR3 1333. However, once the processor was upgraded to a Xeon E5-2690 (2.9GHz), the memory started operating at full DDR3 1600. Stability has been good, and Windows Experience Index score reported was 8.3 with this latter processor.