How to check if logic board is good without lcd Macbook Pro 17" 2007

Sorry I posted in wrong forum (Desktop). So I bought I macbook pro 17" from a person who received it as payment but minus the battery and charger. She said that when she tried powering it on from a charger that the wheel kept spinning and that was it. So I bought it from her for parts minus the lcd. I only wanted the HD and ram. When I went to install HD the same problem as she stated was happening, the wheel kept spinning which was a faulty hard drive. Hmmmmmm..... So without an lcd, how can I check to see if the logic board is good? Im new to macs. I tried putting the ram and a new hard drive in and power up with headphones, but it wouldn't power up from the charger that way and I cant figure it out.... HELP!!