Build Log 7 -- Intel NUC internal mounting in iMac
A very important part of the build is the effective planning and mounting of the Intel NUC inside the G4 dome. There must be enough room for the NUC, all cabling, Rear I/O and in this case, a 2.5" SSD drive. The plan for the build was for the previous DVD bay to hold the Intel NUC, that remains in effect. After much deliberation, I made the decision to proceed with the following goals...
- Keep as much of the G4 Logic board as possible for firm mounting of all components and rear I/O.
- Maintain sufficient clearance for a 7mm or 9mm SSD in the bottom of the iMac.
- Keep maximum height available above the NUC for Sata Connector clearance
- Allow clearance for all repurposing of the G4 rear I/O.
Here's the way it turned out. The NUC will be mounted upside-down for effective access to the headers, memory and Sata port without any removal of hardware. The only caveat is that the NUC fan will be on the bottom, but I don't think it will pose a problem in that configuration.
Square hole cut out of the G4 Logic Board. Most capacitors and all headers are removed. The Rear I/O remains intact, as do all bolt holes for fastening the board down. A small thin rubber pad is glued to each end of the hole for insulating an vibration from the NUC fan. Also being kept is the G4 heatsink sitting on top of the NVidia graphics chip. It is required because it is fastened to the two steel blocks (with bolt holes for the iMac base) that provided an original firm fitment of the base to the Faraday Cage. I have JB Welded the blocks to the G4 Logic board, and also JB Welded the old NVidia heatsink to the original graphics processor underneath it. This provides a solid and original fitment of the base to the bottom of the iMac dome.
Next, I cut a 3.5" x 9" mounting plate which has a dual purpose. The Intel NUC will be fastened to the top inside the dome, and a 2.5" SSD drive will be fastened to the underside of the mounting plate. In this configuration, there is sufficient clearance above the NUC for cabling, and enough room to mount a 7 or 9mm SSD easily while still being able to fasten the bottom cover plate (with the Apple Logo on it) to the base.
With the additon of the NUC mouting plate and rubber insulating mats, the original G4 mounting screws weren't long enough to fasten everything down to the base. I always keep a bag of long UK M3.5 Socket Screws on hand because they match the threads exactly in Apple hardware. Cut to the proper length, they worked perfectly.
Here's what the NUC will look like when mounted upside-down on the mounting plate. This isn't the same D54250WYK that I'll be using in this build, its from an older NUC case. However, there will be little if any difference with the newer model, as the size is very similar. The actual black 'top' of the NUC exterior case will be JB Welded to the mounting plate in a similar fashion as shown below, leaving the underside of the system sitting upward.
Ersterhernd
