I have a G55. Have to say doesn't usually run very hot- left on shelf with not too much clearance above (maybe an inch!?) next to my G68. Never had it trip on me (don't usually listen at particularly high volumes mind)
Such a contrast to my SKY HD box that seems to go belly up at any oppurtunity from overheating and that is with lots of open space!
Hope that helps
Richard

G61R SL, HD621 M6 Front Artcoustic Speakers Diablo Surrounds - All SOLD! :-(
Arcam Power amp for rear channels- Sold
Sonos Surround system- sold

OPPO BDP-103
Virgin TIVO, PS4, Apple TV 4K
LG 65 inch Oled
Sennheiser Ambeo Soundbar