Okay, supra725, listen very carefully and dont waste any more money.
I had my PS3 fail on me, the YLOD. I could have got someone to fix it like you did just to get the thing running again. Don't do it, it's a waste of money. The PS3 will run for 4 months tops and then die again. Instead, accept the fact you won't be able to get that particular YLOD PS3 console up and running fresh like it was new.
EDIT: Before reading below, be sure that there is NO disc in the PS3. If there is a disc there, no worries. Plug the PS3 in but power off the switch on the back. Next, keep your finger on the eject button of the PS3. While holding your finger there, power the PS3 switch on the back on. The PS3's fan will go crazy and the disc will eject.
When I got the YLOD, I accepted my PS3's fate. Next, all I wanted to do was to get all my data. So, I found this neat trick of fixing the PS3 myself WITHOUT avoiding warranty:
http://www.youtube.com/watch?v=kUaCoimoKTk
Don't use this guy's method exactly like he does it. Instead, for 10 minutes, use the hairdryer YOURSELF and move it slowly all the time blowing in the vents. Watch out when heating. Don't blow with the hairdryer on the same spot of the PS3 for too long or else you get what he shows you in the video @ 1:50. After those 10 minutes, give the PS3 a break for 15 minutes (so the plastic can cool down, prevent it from melting.) Then after the 15 minute break, do another 10 minute hairdrying, moving the hairdryer slowly all the time over the vent. Ohh, and remember to do as he does: having the PS3 upside down inside a box when using the hairdryer on it
When you are finished, let the PS3 cool down for 30 minutes. Now when you try to turn it on, it will turn on (at least mine did

). Be smart and don't think you have fixed the PS3, you haven't. You only got it working for an hour, enough for you to do a system backup. Grab yourself a USB flashdrive and go to your gamedata -> copy all you want.
If you manage to make a copy of all the files you vitally want and the PS3 is still alive, grab yourself a big harddrive, a harddrive that can hold up all the data on the PS3. You will want to try the full backup this time. Go to your Settings in the PS3 main menu (XMB) -> System settings -> Backup utility -> Back up. This will back up ALL your data.
For your information: When you restore the data you recovered with the backup utility on another PS3, the new PS3 will deny to restore some data. However, it WILL restore data such as: All your images, music, videos and ALL gamesaves. You will need to redownload the patches for your games and also the games from the Playstation Store you had (if you had any). That's what it won't restore. You restore the data with the Backup utility's option, "Restore".
Hope this works for you the way it did for me!