No no you're right, I completely contredicted myself xD
It will be the RAM size that hurts it though, and the hot GPU temps it seems to have.
YLOD (I think) is very often caused by new "Lead-Free" soulder being used.
Due to recent regs about enviroment stuff.
This newer, weaker soulder seems to be, well, weaker, and after around 3 years seems to dry out and crack. (YLOD) Usually around the GPU.
I had YLOD and fixed it about 30 times myself, it just kept breaking after a day or 2 lol, I could play SD resolutions without a failure though.
To fix you melt down the soulder so it melts back together removing the crack... This does infact dry it out even more, meaning it will be more likly to break again, if you fail on your 1st go, it probably is to late to get a good long-term fix without "Re-Fluxing". Yes, I did massive research when I had a YLOD on my hands.
http://playstationlifestyle.net/forums/showthread.php?t=2376
^^ That guy knows it all lol.
Soulder is a metal that connects the various chips to the main PS3 motherboard, just incase anyone didn't know.
*Forgive my spelling, I can't live without spell checker, and right now, I don't have it xD *