Unlocking 4 cores on Phenom II 550 BE

Check this guide for unlocking cores, it list a lot of the motherboards that can unlock...
http://www.overclock.net/amd-cpus/535501-amd-phenom-ii-...

I just bought one of the new Gigabyte 785G mobos and my X2 550 unlocked easily.

^Congrats! So many people having luck in unlocking cores, It's amazing!  

Don't use Asus mobo for this, they get Hypertransport sync flood error. Go with MSI and forget Asus.

I have unlocked my X3 720 BE to a X4 and I get stupid sync flood error even if the system is stable for at least a day. Prime 95 doesnt report any error at all on all the 4 cores, but Asus mobo got BIOS problems leading for a system crash.

I don't need my 4th core for now, so I will unlock it when I will play game in 1080p.

Or go with Gigabyte!    

I got a personal horror story with Gigabyte, so that leave them out of the picture > 

Seriously, my 965P-DS3 died on me 3 time in less than 12 months at stock settings. I don't want to live that again. I couldn't have my computer for at least 4 months due to RMAs.

In my book, Gigabyte can go to hell, especially after I bought a Asus P5QL pro because there was no way I would put back that joke back in my PC case. I have build the same computer... 4 times... a nightmare.

I don't know...my board is great so far (GA MA770T UD3P) I even overclocked my 550 to 4Ghz on it (and unlocked the two cores)...maybe that board that you had just had a bad design...

Dont know much aout unlock core on phenoms but I can recommend Gigabytes. I've got mb on 945(max fsb 800) which works at fsb266 NB vcore raised +0.3V for over a year now. It's horribly hot but works great. My father sells pcs and staff like that and I can say that there are more defective asus boards than gigabytes.

thats really stange szymek because there was a news article that asus computer are the most reliable on the net, I take the other end of the discussion, I have had both asus and gigabuyte and while gigabyte are good the asus i find are better

None of the manufacturers/brands are perfect. As long as you got what you were looking for and as long as it works, be happy!

Do I need some supercooling+++ to run 550BE that has been unlocked to quad, or will it work with just the original cooling system?

As far as I know the SFE issue has been fixed with the new Bios update.....

My unlocked quad works fine in day to day use with the stock cooler. However, when I run Prime95 on the quad, my temp spikes to 65C within 2 minutes. As a dual core, I run much cooler. I just purchased a GIGANTIC Sunbeam cooler, that I'm planning to install soon. Hopefully, that will cure the runaway temps under full load.

I am running GIGABYTE MA770-UD3 board with phenom II duel cores unlocked to quad and clocked to 3.33 ghz on stock cooler and am getting only 4-5 degrees difference from stock duel core setings

What voltage did you give the CPU? the X2 550 runs fine as a stock x4 B50 with stock cooler 3.1/3.2Ghz, if you are considering a high overclock as a B50 you will need an aftermarket cooler as the stock cooler is too crappy to keep it cool as a quad....