Yeah, your doing it all wrong! jk. When upgrading a new video card or ram, its just a swap and go kinda thing but motherboards are different. Your hard drive has the drivers for the old motherboard and that is why it won't boot the new motherboard. Some of these are very low level type drivers that can cause all sorts of problems when trying to install a new motherboard on top of them.
It is highly recommended to do a fresh install of windows when replacing a motherboard. Now I am uncertain why you can't get into the BIOS, that is a whole other animal. My guess is it could have to do with the new ram and motherboard settings.
So first I would remove all the parts and add one at a time to see if you can determine a culprit. Only use one stick of ram to see if it will boot. Here's a link for troubleshooting:
http://www.tomshardware.com/forum/261145-31-perform-steps-posting-boot-video-problems
Once you've got the BIOS up, and you've achieved some stability then proceed with a fresh windows install. ALWAYS back up your files before doing anything to your PC. This will save a lot of heartache. Next time you want to swap a motherboard, back up everything first and use the Easy transgfer wizard to avoid a bunch of hassles. And yeah, you have to reinstall all the programs; that's just how it goes.