Thanks for the response.
I tried running my sgminer with the setx GPU_MAX_ALLOC_PERCENT 100 command, and noticed no difference, GPU still uses ~1.5gb of memory out of avalible 3gb
Should it have made a difference?
I don't think it makes any difference for algos that don't use the global ram (like groestl) or use it but only for scratch registers (i.e. no explicit buffer allocation) (like x11).
As far as I know, only scrypt uses those kind of buffers in sgminer.