Does it show anything if you hold the Option key at the chime? After several seconds It should show your hard drive (Macintosh HD typically) and maybe recovery depending on your version. If it doesn't show your hard drive then that means it can't see it. Very common (I just fixed one that was doing this yesterday in fact). Most likely the SATA cable. To confirm, pull the hard drive and attach it via USB using a hard drive caddy and hold Option again and then choose the USB drive to boot from. If it boots normally (but probably more slowly) then look for a new SATA cable on eBay or Amazon. Buy an OEM one though, don't mess around with off brand ones.
Other things to Try:
Booting in Safe Mode
Boot in Single User Mode and run fsck -fy at prompt