That would be like closing the golden gate bridge to prevent speeding. It does nothing. Being that this game is supposedly optimized for 4k, the textures will have to go along with that. Uncompressed textures will have a large file size, especially at 3840 x 2160. Let's hope they don't follow...
The main benefit in terms of cost is the fact that you can cut out the labor costs. You can cut out the cost of putting the machine together that normally comes included in a pre-built system.
However, you can easily have the cost rise if you don't buy parts all at once. I recommend saving...
the tRL settings can only be found in newer versions of the BIOS. I found it only in the newer 2011 versions of the BIOS (can't remember the exact one) so just upgrade to the latest BIOS (8/2/2011) and you can find the TRL settings at the bottom of the memory settings, under the extensive list...