dual channel problems

After killing my old mobo last week I ordered a new one which I got on friday. I was finally able to install it today after doing the vdimm mod to it and adding heatsinks and whatnot. I set it all upm turn it on, and it doesnt post. After playing around for a while I remove the 2nd ram stick and it starts up fine. I shut down and try the stick in the other dimm slot and once again it doesnt post. I switched sticks and it works fine with either in the 3rd slot. However, if I have any stick in either slot 1 or 2 it doesnt post or anything.... Any ideas?

Well, after removing the mobo and discovering a large blob of solder on the ICs next to the dimm slots i almost dropped dead. After spending a good 30min cleaning them up and then redoing my vdd mod which was also kinda messed up, I booted back up with 2 sticks in dual channel and both the dimm slots and my vdd mod now work!!!! Everything is back to how it once was. You have no idea how happy I am now, haha. Ahhh Its alive!!!!! Now to see how far I can take this baby.