Halo: Reach doubled sales of Xbox 360 in the UK last week, according to Gfk-ChartTrack.
The firm's director, Dorian Bloch, said the game had a "marked effect" on hardware sales with Xbox 360 console sales "up 99 percent" for the week ending September 18.
GAME's limited-edition Halo-themed Xbox 360 also played a part in the hardware surge, according to Eurogamer.
That's not bad as far as hardware sales are concerned. Not 1000 percent, but not bad either.
Reach moved around 300K copies during its first 24-hours during its UK debut last week, and had the fifth biggest game launch week ever.
Halo: Reach will get matchmaking sometime next month.