still thinking through the issue -- dont hate me with this suggestion, but is your firewall allowing the program through? it could be possible the local app boots up, simcity.exe., but then when it tries to phone home to EA it gets stuck in a firewall thing? that would match the When for why its locking up...
re Diag: dxdiag can be run by >>> Click on, "Start Button". Click on, "Run". In the pop-up window enter DxDiag and hit ok. The DirectX Diagnostic Tool pop-up window should appear. Click on, "Save all information".
from that diagnostic list a hardware check may help... post it here please - in another simcity thread i noticed a guy with a six year old motherboard bios, and in some ways super outdated sound drivers off the mobo can relate to bios... its a stretch but good reason to see the diag posted?
i would not think [if this isnt happening anywhere else] that your video card is at fault. or any hardware. for me this fault is 1% of boot ups and not 100% as in your case, so i have experience it but not locking up pc completely. i do have to almost always hit ALT-F4 to exit the game when it kicks me unexpectedly out of the city i am playing saying "lost connection to ea servers".
its that outside connectivity which makes me think firewall or similar and not hardware. for example i would chase memory/RAM/HDD if this was in a couple of your games - locking up.
Repair is a function that appears when you right mouse button your game in My Library. i have used that a lot for thing like this and am surprised when it finds and corrects a corrupt file...
finally in the My Library > Game Properties (right mouse on your game title) uncheck 'Enable Origin In Game for SimCity™: Complete Edition', can't hurt and mine is off...
