No video on GA-78LMT-S2P (version 4.0) boot

[ajkuiven]

Hi everyone,

A couple days ago, I purchased the board in the title for a new build.  I assembled everything, went to turn it on, and no video.  Hard drive spun up, fans were on, just no video.  I checked all connections, still nothing.  So, I start removing components one by one to see if anything was conflicting or faulty.  I replaced different things (monitor, power supply, etc.) with other ones just to make sure those weren't damaged at all.  Still nothing, so I figured I just got a board that was DOA.  Earlier today, I got a replacement.  Before hooking anything else up, I just attached the power supply, the power switch/reset pins, and a monitor.  I just wanted to see if the mobo was any good before I got any further.  Turn it on, still no video.  At this point, I'm stumped.  I know I didn't damage it attaching everything, and it seems unlikely that I would get two boards in a row that were bad.  Any help would be appreciated.  Oh, and it's a 450 Watt power supply if it matters, and yes I tried clearing CMOS.  Thanks.

[Dark Mantis]

Hi and welcome.

A few more details like makes and models of components would help greatly to build up a picture of your system. Are you using the onboard graphics or a discrete card ?

[ajkuiven]

OK, here's a listing of everything that will eventually be used:

Mobo: GA-78LMT-S2P (version 4.0)
Processor:  AMD Phenom II x6 1055T (125 watt)
Graphics: Radeon HD 6670
RAM: 2x 2GB Micro Center DDR3-1333
Hard Drive: 250GB Hitachi 3.0GB/s Sata
Power Supply: IC-PSU-US-2545-DW

During my first test of a brand new mobo with the above model number, I was using the onboard vga slot.  The only things attached were the main power pins, the 4 pin power, the pins for the on/off switch and a monitor.  Obviously I would get a nifty no processor message, but I just wanted to see if anything came up.  No video.  I then proceeded to try adding components one at a time, and trying different video output slots as well, both onboard and discrete.  Still no video.  And yes, I made sure I didn't shock or drop anything on assembly.

[Dark Mantis]

With no CPU inserted in the slot nothing is going to work. It won't even POST.  Install the CPU with the HSF a stick of RAM and then try and you should get a bit closer.

[ajkuiven]

Yea, I had eventually tried with everything attached, ram, cpu, etc. but it hadn't worked.  Turns out it was the power supply.  I tried a third one, this time a newer model and it booted up fine.  Both the others I had tried were in builds using dual core.  Looks like their specs weren't updated enough to run a hex core.  Now I know to buy everything new I guess.  Thanks.

[Dark Mantis]

Well glad to hear that you got it working in the end anyway. It is surprising how often the power supply is behind the problem in the end.