Okay, how about some lateral thinking ? A gaming rig can never be really power efficient and a power efficient rig can never do good gaming. If we can separate them into two different requirements, you can come up with two machines that take the same space and meet all your requirements and your budget of 40k.
Rig 1: Antec NSK4400 Cabinet(1.5k), Corsair VX 450W (3.5k), Core2Duo (6k), any good motherboard (4k), 4GB DDR2 (3.5k), a 1TB sata drive (4.3k) and a good DVD burner (1.2k) with a Radeon 4850 card (7.5k).
Net total of 30k. Power usage is approximately 120-220watts.
Rig 2: Build your own mini ITX rig. Get the MOREX T3300 mini ITX case (3.5k) with inbuilt DC adaptor, a Intel Atom dual core 330 board+cpu (4.5k), 2GB DDR2 (1.5k), 80gb laptop hard disk (2.5k).
Net total of 12k. Power usage is approximately 30-50watts at all times and the machine will be great for all activities except gaming. Also great as a 24 hour downloading rig.
See :
Panache
So there you go. The second rug will be the size of a harry potter book and will be attached behind your LCD monitor using the standard VESA mount. And both the machines connect to the same LCD. You use the smaller one for all activities and boot into the power hungry monster only when you need to game.