I just bought a computer I cant play garrys mod I tried looking at more views but it didn't let me I try and try but it still doesn't let me play it

You may need to install DirectX Runtime June 2010, which is a optional update that a lot of games need.
Even my Lexmark printer requires it... I will include a link to the full installer...
This is a self extracting package. It will extract after double clicking on it so be sure to note the location where you\it extracted.
Then open the folder and double click DXSETUP.
You may have already tried this with the web installer, but this is the full file... It might work better.
From what I can find, the atiuxpag.dll is related to switching from Integrated Graphics to Dedicated Graphics in a Laptop dependent on whether AC power or battery is being used.
It does seem to be dependent on DirectX 10 in some fashion. This link is primarily DX9 and DX10 stuff, so it might help.
http://www.microsoft.com/en-us/download/confirmation.aspx?id=8109