While not a highly kept secret, AMD has just released the ThreadRipper 1900X HEDT (high-end desktop) processor. This 8-core, 16-thread processor is targeted at users who want to make use of quad-channel memory bandwidth and the added I/O which the ThreadRipper platform brings to the table. The chip is priced only $50 higher than the 8-core, 16-thread Ryzen 7 1800X at $549.
You do get higher clocks though with a base clock of 3.80 GHz (compared to the 3.60 GHz of the 1800X), 4.0 GHz boost, and XFR adds 200 MHz to the boost clock if you have sufficient cooling. You get a full quad-channel DDR4-3200 memory interface, with support up to 2TB of memory, and ECC support. There is even unofficial RDIMM support.
You also have a full 64-lane PCI-Express interface with the same configurations as the higher 1920X and 1950X. The chip has 16 MB of L3 cache and has a rated TDP of 180W.
Below are AMD’s internal testing numbers.