If you have read our extensive Threadripper 3990X review, you will have noticed that we used an updated version of the Zenith II motherboard from ASUS, the Zenith II ALPHA. As mentioned in this review, the boards are the same aside from increased power stages to support more and higher frequency memory.

ASUS will update two other TRX40 motherboards that will receive an update, the boards are the ROG Strix TRX40-XE and the Prime TRX40-Pro S. Make no mistake though, all TRX40 motherboards are perfectly fine for the 3990X with wide memory frequency and CL support. For the XE we understand that sixteen TDA 21472's have been placed in 8 phases, for the Pro model the precise configuration is unknown just yet. Both boards have a new VRM for the memory basedon Dr.Mos chips.

ASUS notes that the Zenith II Extreme Alpha is guaranteed to handle eight ddr4-3200 modules with a total capacity of 256 GB and CAS latency values of CL16, problem-free. We have yet to see any motherboard actually running into problems whatsoever, so the motives from ASUS might be marketing related 'to put improved boards out there compared to the competition'. Again, all TRX40 motherboards with a firmware update can run 3990X as well as up-to 256GB of quad channel memory.

ASUS ROG Strix TRX40-XE and Prime TRX40-Pro S to get updated Power delivery for memory as well