To my surprise, it is indeed possible! … … An xda-developers forum contributor with the nick name Adenin came with a nice tweak that can change the FM band range in HTC Artemis. The registry modifications are the following:

HKLM\SOFTWARE\HTC\FMRadio\FMPlayer\Band
0 = 87.5 – 108.0 MHz
1 = 76.0 – 108.0 MHz
2 = 76.0 – 91.0 MHz

You can also set frequency direct in HKLM\SOFTWARE\HTC\FMRadio\FMPlayer\ChannelValue = MHz * 10 (=> 1100 = 110.0 MHz )

Source: xda-developers