My build is.. i7 920, intel DX58SO Extreme, with G.Skill F3-10666CL7 RAM 3GB (3x1GB).
The issue is that when i put all three of the ram modules and boot.. it reboots after 3 to 4 seconds and theres no display, but when i put 2 modules it boots just fine without any problem.
I checked if my ram modules have any problem by booting on one ram module each.. and all my modules are good no problem in the ram.
I found out that the third ram slot (from the top) has the issue, if i put the third module in it and boot it reboots in few seconds without display.
My system has been running smoothly with 3 modules from past 3 to 4 years. I just upgraded My GPU a day back from Sapphire ATI Radeon HD 4850 to Sapphire HD 7870, no issues there too coz i ran my system after upgarding for a whole day. I just did reassembling of all my components in my rig and did rewiring, problem started after that.
I tried for a lot of hours to fix it but its just not happening.. im running on 2 modules now.. plz help me with this.. i miss my 3rd ram module so much... 
Hello Pawan,
I understand that after you reassemble the system your memory slot stop working.
I recommend you to start by testing your motherboard out of the chassis to discard any possible grounding problems that may be causing this behavior.
Regards.
PV
hmm.. never thought of that.. ok im going to try this, ill try booting with my motherboard outside. ill do it in a day or two cause i got to finish my work first and dont wanna screw up my system before ..
but hey if there was any grounding.. can it affect only one specific ram slot?
ill try it and let you know.. THANKS A LOT Victor...
i tried booting my system with my motherboard outside the rig.. problem is still there.. then i updated my bios.. problem is there.. but this time motherboard beeps thrice then stops and beeps thrice again.. and this process goes on..
I’m having the same problem with 3x2GB GSKILL (F3-12800CL9T-6GBNQ).
As soon as I put all 3 in triple channel the computer reboots after 3 to 4 seconds and there’s no display. When I put 2 everything works.
I tested all modules separately with another computer and they all work fine.
