I'm done I give!! Ps3 issues?

So I recently got the YLOD during some black ops play. I sent it off to this company called gophermods I thought they would be able to fix it. Well they did, however now I can't get the HDMI cable to work to show the video or play some audio. I've tried to reset the video on it and do that soft file system restore thing by holding the ps3 power button. To no avail. I don't have any other cables with me so if I could get any advice it would be helpful. Also talked some schmuck at Sony into believing that I just received it from them but only for advice there wasn't a way in hell that I could get a replacement from them. Well thanks in advance!