Look at settings for your video adapter, under Control
Panel|DISPLAY|SETTINGS (examine the choices under ALL tabs).
If gamma does not appear, then it is likely that the adapter driver does
not support that feature. Check the chip or card manufacturer's WEBsite
for an updated or alternative driver.
If you are unfamiliar with driver updates, it may be wise to enlist the
help of a tech or friend who is.
Look at settings for your video adapter, under Control
Panel|DISPLAY|SETTINGS (examine the choices under ALL tabs).
If gamma does not appear, then it is likely that the adapter driver does
not support that feature. Check the chip or card manufacturer's WEBsite
for an updated or alternative driver.