Motherboard installed in computer case;
A) Keyboard Jumper Block
3-pin jumper block, Top of motherboard/ left side. Near the mounting hole, and 4-pin ATX +12 Volt power cable connector,
GENERAL example of a 4-pin ATX +12 Volt power cable, and it's respective connector on the motherboard,http://www.playtool.com/pages/psuconnectors/connectors.html#atx12v4
[ This power cable MUST be plugged into the motherboard.
It is power for the Intel processor ]
3-pin jumper block.
Starting at the TOP coming down;
Pins 3, 2 and 1.
Jumper cap should be on Pins 2 and 3.
(Enables the Keyboard wake-up feature. Factory default setting is Enabled. Pins 2 and 3)
B) Clear CMOS Jumper Block.
BOTTOM right corner of motherboard. 3-pin jumper block.
It is to the Left of the bottom/left SATA connector.
It is immediately to the Right of the motherboard mounting hole.
Starting at the Top, and going down towards the bottom edge of the motherboard;
Pins 3, 2, and 1.
Jumper cap should be on Pins 1 and 2.
When you changed the SMPS, do you KNOW for a fact it is a good one?
Did you plug the 4-pin ATX +12 Volt power cable, into the motherboard?
What COMS setting/s did you change?
I would go back into BIOS Setup, and set that menu screen back to the factory default settings.
[ Load Optimal Defaults ]
BIOS Settings Glossary,http://download.intel.com/support/motherboards/desktop/sb/biosglossary_v18.pdf
[Motherboard manual - http://www.intel.com/support/motherboards/desktop/dg41wv/sb/CS-031417.htm