Xbox just beeps wont turn on

[DarkAlex]

So I have installed a demon and a coolrunner 3 lite on my Trinity Xbox, I have flashed the coolrunner got the CPU key, and everything went fine, and the console worked fine for all day, booted to rgh and retail without any problem.
Then in the evening, I unplugged the power supply and came back after 2 hours, I tried to turn on the Xbox and it just won't turn on it just beeps, the cr3 doesnt even try to glitch.
So I tried to boot to my retail NAND and it booted up, then I turned it off and tried again to boot to the retail NAND, this time it turned on and showed me a black screen with problem e79, then i tried on the third time and as the rgh it just beeps, won't turn on, won't start the fan, etc..

I have rechecked everything, the solder looks fine, I don't know whats the problem
my soldering pics:

 

[SoulReaper223]

we need pics

 

[DarkAlex]

K, Posted the pics, but i really don;t think it's the soldering cause it worked for all day long, it's really starnge

 

[DarkAlex]

Alright, so I tried to read the NAND, and got manufacturer error FF, probably there is a short somewhere, I will recheck the soldering, again

 

[Martin C]

There is a very good reason why DemoNs are shipped with a card, advising they're for experienced installers.

Before you posted for any help, all continuity checks should have been carried out as per standard procedure. If you don't know what they are, search the forums as I've mentioned it at least a dozen times.

 

[DarkAlex]

Well, I'm learning to be this professional, and the first thing I did when I got this problem was to check reading the NAND and It worked just fine

 

[Martin C]

Then you need to learn the basics first, which means learning to use a multimeter. We're here to help you, not to teach you.

 

[TheGlow]

Well, I'm learning to be this professional, and the first thing I did when I got this problem was to check reading the NAND and It worked just fine

I started with a Demon install as well. With an analog multimeter without a continuity tester.
Very fun checking each point and hoping im still holding the right spots while looking over to see if the needle is jumping around.
I still havent gotten a new multimeter yet.
But yea, double check. It might have been fine that one day with something semi loose and then eventually popped off.