Have a Dell Inspiron 5150 laptop. On power on, hear heatsink fan, monitor shows blinking cursor on black screen. No Post indications, no Dell welcome screen or Windows boot. Recently changed motherboard and recompounded cpu/hs (artic silver). Laptop booted into windows a few times but get same result, black screen w/ blinking cursor. Would appreciate any help.
Does your BIOS have a set of beep codes it uses if it cannot initialize video correctly? Are you using external monitor? If so can you switch to laptop lcd? (or visa versa).
Pull memory, see if you can get the BIOS to complain about the missing memory (assuming its not soldered on board). Follow dell procedure to re-init bios (reset to defaults) On pc this is via jumper, no clue how to do on laptop. remove anything attached (external mouse, keyboard, dock printer, network). Remove disk. remove anything in mini-pci slot if you have one (like a wireless adapter). Get as close as possible to just he CPU and MB. If you can't get it to post at all then your laptop is toast. Eventually you might want to re-do the MB install and thermal paste on your CPU.
Can you verify the sequence of events. These are incompatible (duh). I'm guessing you mean that for a while it would boot, but eventually it would not even post.
(1) "No Post indications"
(2) "Laptop booted into windows a few times"
If the new MB uses a different chipset/video and your copy of windows doesn't have the right drivers you might end up with a blinking curser but you would have POST'ed and would have been able to get to the bios.