It's id Tech 4, have you tried games like Doom 3, Prey, Quake 4, ET: Quake Wars? They're all basically the same engine, all just slightly differently modified. If you can run all those games well enough, you shouldn't have any trouble at all with Brink. Black Ops and Modern Warfare 2 are highly modified id Tech 3 engines, so they would also give some sort of reference as to how well you can run it.
The id Tech engines are known to be very scalable, so if your rig has troubles, you can always disable some of the heaviest features like shadows and depth of field etc. (I at least hope so!
If the console is disabled and the graphics settings are crazy, I might cry a little.)
(Edit: err, r-e-t-a-r-d-e-d got censored, what is up with the filters here?