I finally had a chance to test all the ram, all chips individually test fine, depending on slots. The Primary slots (under the keyboard) would only accept either or both of the original chips (16gb 3200). The other 2 slots (in the back) accepted all 6 chips. So with the factory shipped ram - i was maxed at 96 gb 3200 speed. I decided to buy and try 2x32gb 2933 RAM. Success. I can place this RAM (2x32 2933) in the Primary slots in the system, and the 2x32 3200 RAM in the secondary slots. 128gb x 2133 is what BIOS now shows. So Its something to do with those front slots accepting 2x32x3200. But no worries - this config works just fine! I am happy with the setup as is. Latest BIOS and drivers are all installed. Just an odd deal
Got a weird issue with installing RAM in new Precision 7550.  Trying to max it out (128GB). Came with 32gb (2x16gb) installed under keyboard. 4 new chips, 32gb each.  I can install any of the 4 chips in the slots in the back of the laptop just fine, it will then show 96GB of RAM. But replace the 2 16gb chips with any of the 4 32gb ones - and I get the 2 amber 5 white flash (memory error). Have reseated and swapped them around, all 4 chips work just fine, just the system does not like you changing the 2 under the keyboard. Any special system reset that needs to be done to accept these?  I am at a loss for why they cant function there, but soon as I stick the old chips in - back to solid. Thanks!
7550 RAM Issue