Installed new screen, backlight on, no picture

Hi, I just finished installing a new screen to replace my old cracked screen, but it doesnt show the display. I have an SE Inspiron 17r 7720, my old screen says B173RW01 AU Optronics on the back, and this is a link to the new screen: https://www.amazon.com/gp/aw/d/B0113NMAFU/ref=cm_cr_arp_mb_bdcrb_top?ie=UTF8

Also side note, I plugged it in into the TV I was using to substitute my monitor while it was being shipped, and the resolution now makes it square instead of it fitting the entire screen. Any suggestions? Thanks!