I’ve just added a HDD with (slow) 5400rpm because I would increase some space on an not so important drive (it’s more storage than project workspace) and thought I would give it a try.
20GB UE5.3 Project around 6700files startup time:
SSD NVME M2 (Corsair MP510): 21 seconds
HDD 5400Rpm (WDRed 4TB): 21 seconds
Both are single drives (no raid).
Rest of the specs:
32GB Ram DDR4 (3200)
AMD 5600XCPU
4060ti 16GB
Whatever takes time here it seems its not the harddrive. At least not for the project files.
Note: In my last test the HDD was 0.3 faster. I did not really expect that. But I guess it was just my finger on the stopwatch. Note I’ve Windows and UE5 program folder on a SSD either so I’m not sure how the startup time looks like if UE5 program is on HDD as well. But as far I remember the startup time was pretty much the same as well in the past.