lga 775 system with a gtx 780 no image on screen.

1. i hope the board now has a cmos battery in it.
2. try going through this.

If you have a conventional PCI-based GPU, remove the 780 and try using that to get into the BIOS and try to find an option for primary video adapter, set it to PCIe, then reinstall the 780. (This requires CMOS Battery.) If you don't, then try/borrow another, and possibly older GPU.

Did you make sure the power connection is in the GPU? Have you tried a different port on the GPU display output? Different HDMI/DVI cable? And try a CMOS battery as well.

Also, is the RAM ECC or no? And try one stick of RAM in different slots, and swap them out. Do you know what BIOS version the motherboard has, and do you have an older CPU around if you upgraded it? If so, try the older one.

Honestly I doubt that a 775 motherboard would output video to the HDMI port on a PCI-E graphics card. Usually only the first "port" on the card is used and to be absolutely certain, use the on board mobo graphics connector if there is one (Usually there was). The primary port, or the mobo port, is 9 times out of 10 a VGA or a DVI slot (definitely DVI on the 980 graphics card - VGA wasn't obsolete in the 775 age yet).

Of course there could be other issues, such as the CPU not getting powered properly and whatnot, but I'd be willing to wager a semi-large bet that the graphics just aren't being output on the HDMI cable. Even in modern computers I find myself hooking up to port one DVI to perform initial setup on the rig before switching it over to HDMI or displayport.


EDIT: I looked up your mobo and you don't have a graphics port on it. Which is fine. Hook up your monitor to the DVI port on the graphics card instead of one of the HDMI ports and you should be all okay.

the cmos batter is cr203 flat round battery. on the mb make sure it has the newest bios file. rule out a bios bug with the gpu.

pull the gpu and one ram stick see if onboard video comes on if not see if someone has an old 8800 or 210 video card or an older and gpu for testing.

You've been thorough then! If you are getting no beeps from the motherboard or any display on any port it's not even reaching post. That's a CPU, motherboard or powerfail. The one time it has happened to me it was because the 4-pin power cable to the CPU wasn't plugged in correctly or because the wrong plug from the PSU was used (some PSUs have two CPU plugs, one for older standards and one for newer - if one doesn't work, try the other). It could just as easily be a different error though so I'm afraid it's a bit hard to diagnose from here.

Most motherboards have some kind of diagnostic tools to troubleshoot (usually beeps or LEDs). Check the manual to see if you can get any help from there, otherwise this'll be one tough nut to crack without changing one part at a time.

EDIT: Also, pop a battery in there as more advanced BIOS will want to save settings to allow new boot features, and while that probably isn't the case here it'd be stupid to not at least remove it from the equation.

Best of luck! Can't guarantee I'll be around for the climax, but hop you get things running!

Wow, quite a bit of support you've got here. Sorry for my delayed response, I'm about to hit the hay. But I will have you know that aside from what I've already suggested, I don't have much more of an idea for what it could be. But I do know that if you're using a newer CPU that the motherboard is unaware of without a BIOS update, it could definitely cause issues. So if you can, as long as it's not too much trouble on your end, try placing an older model CPU in there and see if it makes a difference, along with the suggestions of the others here.

Same with the GPU, if it's too new, it could be a possibility that the motherboard can't detect it without a BIOS update, so trying an older GPU could be an option if you can borrow one. A PCI-based one could help with troubleshooting too. Though I don't want you to waste money on something that may or may not work, so if you can borrow most of the things you need, that would be best. Unless you can get them locally and can easily return them if need be.

You might also check the physical condition of the motherboard as well. Are there any blown or bulging caps? And do any of the pins in the CPU socket look bent or out of place?

EDIT:
I'm also reading on issues with that particular motherboard model, and I'll fill you in later when I learn more, but you might also try DDR2 RAM instead of DDR3 and see if it helps. Perhaps the RAM is also too new....

EDIT 2:
Sounds like the MB could have some issues with DDR3, so definitely try DDR2. You can download the motherboard manual to find more information on compatible RAM, such as the amount of pins, buffered or not. Also low-density and high-density RAM could play a part in it. I don't know much about densities though. Perhaps someone here knows more about RAM than I and can help you further.

You can do some searches in Google for you motherboard model to try and find similar problems with being unable to boot/no display/RAM/CMOS, etc, etc.

EDIT 3:
Also sounds like some kind of overclocking setting in the BIOS could be screwing things up. I'll give a few links for you and the others to read through. Related to RAM, DDR2/3, and the overclocking in the BIOS, etc.

X48C platinum won't boot with recommended DDR3
MSI X48C Platinum with DDR3...
Stumped! Recommended Corsair memory won't work...

Hope this helps a bit, and I wish you the best of luck! Hopefully you get it running, and I'll try to help out if I can. And definitely take a look at those links. Seems to be pointing a finger at the RAM, though I could very well be wrong.

sorry for my late response. of course, you can pm me whenever you have a problem.
anyway, i don't think anyone has mentioned this yet, but what frequency ram is that? Here, it says only 800, 1066, 1333 or 1600 is supported.
also, regarding the psu 8 pin cable, make sure you plug in the one that says cpu on it to the motherboard and the other 8-pin into the 780 (for the gpu, you need to plug in both a 6-pin and an 8-pin).

Sorry it didn't work out for you. I've had two builds so far that haven't exactly worked out. An AMD K6, and a Pentium 4.

On the K6 build, I couldn't get the GeForce 6200 PCI GPU to work alongside the ISA sound card, yet they both worked separately, they refused to work together. One long, two short beeps I believe it was. I tried messing with IRQs and memory addresses to no avail. No image on screen except with integrated video. Motherboard was an ASUS P5S-VM, HP Pavillon 6640C model. Granted I didn't try different RAM.

On the Pentium 4, it would pass stress tests perfectly fine, but it kept freezing during games. Could've been the motherboard, CPU, RAM, PSU, I'm not sure. Motherboard was an ASUS P5WD2.

I'm using the same PSU I used for the P4, and now I'm running a Core 2 Duo E6850 and a GeForce 7950 GT with 4GB PC2-6400 DDR2 Hynix RAM. I may try to upgrade the GPU and CPU in the future, and try to get some cheap 4 GB RAM modules to try and coax the MB (DG43NB) to use 8GB max. I don't know what the difference was, the RAM, CPU, PSU, MB, or what. But the Core 2 Duo also uses less power than the Pentium 4, so there's less load on the PSU.

At any rate, I wish you luck in getting your money back, and I hope your next build works out splendidly. You always have the forum for help. You might keep the 780 GPU and the CPU in case you decide to try again, but that's your choice.

I wish you good luck with the build.

It was a Pentium 4 530, hyper-threaded, when it froze it was permanent, requiring a hard-reset. The audio would get stuck in a loop, and this happened in two different games I tested. One of which was WolfQuest 2.7.1, every time I tried to run the load the game after creating my wolf, it would freeze the system. It also froze in TES IV: Oblivion, after I got out of the sewers and faced the water, or walked into it.

The main reason I was going for a Pentium 4 was to play older XP-era games.

yes, it might be the ssd, as that "insert boot media" thing (most likely) means something is wrong with either the motherboard or the ssd.

on old mb most time is a swelled cap that starts to fail causing lock up if the temps are fine and power supply is fine. it could be cap or voltage reg on the mb.

if you read op's last post, you'd know that he replaced the motherboard and cpu and yet the problem persists