As the topic suggests, I have the 3 RROD with no error code of any sort with the 360 fires up. I purchased a repair kit and removed the XCLAMPS and also purchased the Whisper fan for the rear of the 360. I also purchased the XCM Cooler ver 2 (not happy with it but that's another topic).
Everything fires up but I still get the 3 RROD and no video or error code. I think I am going to try the penny trick on the memory but thought I should ask for suggestions before going any further.

I am a PC builder so I am certain I gave enough torque to the CPU and GPU screws but I suppose I can double check before buying another xbox.

UPDATE:
I took it apart for the 2nd time. I tightened up the heatsink screws and even double checked they all had the right # of washers and the right order they should be placed. I put the mobo back in the case, plugged in the DVD drive but no fans and turned on the 360. I got the 3 RROD followed by 2 RROD on the left side. I let it sit for two minutes and turned it off. I actually felt heat this time (the first time I didn't). So, I was optimistic.
I put it all back together, fired it up and BAM, 3 RROD. I think my heart imploded at that time.

What I am going to try next is, take it all apart, leave the DVD plugged in, unplug the fans, and see if I get the 2 RROD again. If I do, then I'll plug in the WhisperMax fan, and then fire up the 360. If it works, then I'll plug in the XCM Core Cooler ver 2. I am wondering if something is pulling too much juice from the board.
I will update my results when I am finished.

UPDATE #2.
I'm screwed.
I have unplugged the fans individually and fired the 360 up. Still get the same problem. I am probably going to buy a new XBOX as I can't imagine what else I can do to fix this.

Allowing the xbox to bake in its own warmth does nothing, you may aswell breathe on it. its not going to melt the solder. even if you do get it working by x clamp, it wont last long.

Whenever I do a repair I always get green lights unless the mobo itself it past repairing.

Ok. I just tried to bake it using the heatsink sittin half on the DVD drive and the other half on the CPU. With the WhsiperMax, it lasted 11 mins before the 3 RROD went to 2 RROD.
I then powered it off and waited 10 mins and still got the 3 RROD.
I even plugged the AV cables instead of using the HD component cables and still, no video. When holding the sync button and pressing the eject button 4 times, I get this
try 1: all 4
try 2: 1 in upper left
try 3: 1 in upper left
try 4: all 4
after that, it goes back to the 3 RROD
I just googled what I found and apparently, this is a 0110 error involving Ram issues. What is the best or should I say, permanent solution for this? If there isn't one, then I'm done with it.

you can do the eraser trick or 12 penny trick what u do is get one of those white eraseres from cvs or sumthin and cut it out to ruffly the same size as those bandaid lookin things that are on there and then re assemble also u can look into the heat gun trick to try and reflow the solder abit

u can also check this post
http://forums.xbox-scene.com/index.php?showtopic=484726

I did a penny trick on one of mine when it was ram chip errors. It's still working and that was about a year ago.
Just do enough for pressure but not enough to warp the board more.

You are getting 0110 error which is a RAM problem. Try heatgunning the RAM chips and putting it back together, don't bother baking it with the fans off, it won't help. Make sure to remove all the heatsinks from the board before heatgunning.

For Ram issues i recomend XCM Heat Pads Availible for www.shopneo.co.uk