Did you reload the OS? Changing boards can cause that sort of windows issues.
I recently acquired a studio 1737 with some known issues. First being the DC port being broke. So i bought a new board off of ebay, put everything back together plug the power adapter in, and noticed no light came on in the corner. I continue and press the power button and the amber light flashes 3/4 times followed by white. no beeps tho, it says unidentified battery, and i continue anyway. Next the windows vista bar shows loading windows for about 1 second, then restarts all the way back to the bios splash screen. Can anyone help?
i also try avoiding the battery issue by running the laptop with no battery, and i still get the same boot problem