I know that this was sort of covered a few pages ago, but not in any comprehensive sort of way- is there any possibility of fitting the new HDPlex 400w AC-DC, the 400w DC-DC, and the U9s? Let's start with the assumption of no 2.5" drives to make that easier for starters.
I don't think this would be possible unfortunately, the AC-DC unit is quite deep and I don't think there would be sufficient gap in between the 2 units to fit a tower cooler, especially once you factor in the socket position needing to sit exactly in the middle of the gap.
Take a look at the photo below, the HDPLEX AC-DC can only be mounted to the front panel, which means the HDPLEX DC-DC would need to be swapped over to the rear panel:
So you would end up with a configuration similar to this:
Another layout option is to instead mount both the HDPLEX AC-DC and DC-DC units to the top panel, which increases the CPU clearance up to around 90mm compared to the SFX layout, with the added benefit of potential to install a rear 92mm fan, like this:
I'm saying it fits directly under the SFX PSU in similar fashion as a normal air cooler, except the radiator wouldn't have any mounting points for screws ....it would just be sitting there. Measurements are fine all-around with a slim 92mm attached to it, tubes are extremely bendable.
OK understood, however I'm not sure I see the advantage to this setup over for example the NH-L12S air cooler. One of the major advantages to AIO's is that you can dump the CPU heat directly out the case which prevents heat re-circulation and in turn keeps temps lower during prolonged heavy usage, but in this setup the heat will be being dumped back into the case in a similar fashion to a standard air cooler.
I've not read any test data for the 545LC 92mm AIO, so I can't really comment on how well it would compare against something like the NH-L12S in the same conditions, it would definitely be an interesting experiment to find out, but my gut is telling me that you won't see any significant improvement in temperatures compared to a similar sized heatsink that is conventionally air cooled.