So I thought anyways. I hard bricked my AT&T Samsung Galaxy S3 (sgh-i747) faster than you can say "oops." At that point my phone was a paper weight. It would not turn on, couldn't get the light in the top left corner to even blink showing me that the battery was in fact taking a charge. I couldn't get it to do anything period. So I got another S3 and moved on. My AT&T Galaxy S3 sat in the bottom drawer of my dresser for the better part of a year EASY!!
Yesterday I pulled it out and my G/F somehow got it into Download Mode. At this point I tried everything. I tried wiping/factory data reset/ fromatted everything just in hopes of getting a successful boot up. I tried Multiple Odin version with a CF-Auto-Root.*.*.tar.md5, also root66.ATT.*TAR.MD5 and atleast 2 other .tar packages and the bootloader for AT&T. Nothing would work via Odin. When I power on myu phone it was going directly into download mode saying "NO OS INSTALLED" I finally downloaded Android 4.4.2 KitKat VanirAOSP ROM from the link below
I then put the ROM and Gapps zip files onto my 32gb sdcard using a microSD reader. Once both zip files were copied to my sd-card, I right-clicked on the the SDCARD drive inside "My Computer" and selected to 'Eject SDCARD'
I then put the SDCARD into my AT&T sgh-i747 and put the phone into CWM Recovery "Philz Touch 6"
From there I did standard wipe, then flashed rom and afterwards I flashed gapps. Phone is back up and fully operational ever since. I wish it hadn't only taken me so long to find this out. :P I hope this may help someone. Can anyone else confirm this method?