A no POST is one of the hardest things to figure out. Especially if you don't have spare parts to swap in and out. It sucks to have to pay somebody to look at it, but sometimes you have no choice. If it's a quick fix, it shouldn't cost much. It's either RAM, CPU or Motherboard. RAM is a quick swap, that would be what I looked at first. Then CPU. I hope it all works out OK for you.
Thanks for your time and support!
Power supply is usually at the top of my list for situations like this. Motherboard is number two when it was stable, but now won't POST. Bad RAM usually causes other issues as a hint that something is wrong. And it's usually only one stick that goes south.
It sounds to me like you have a hardware issue somewhere. Are there any beep codes when it fails to POST?
I would suggest a complete teardown and boot up after each component is installed. Its ok if the system beeps in an expected sequence to tell you there is no ram. In fact that's good.
Have you tried out of case assembly? Assemble the core comps on an ESD safe surface or test bench case and see if it works there?
I once had a system that would fail post, post and not show all the ram, post and show all the ram, post and show portions of the ram and most USB ports were DOA - not responsive. Kind of like rolling the dice each time I powered it up. All of this was due to the fact that my HEATSINK (Noctua) had shipped without four neoprene washers that went on each of the four posts and sat between that back of the motherboard and the heatsink mount plate. I went to home depot and bought four washers for .87¢ and this resolved what had been several weeks of just wacky behavior. This all came about though as a result of a complete teardown and chatting with others on a forum like this one.
Little .87 cent washers were the difference between solid reliable system performance and total instability. Anyway just saying, you just never know what will cause a ground issue and prevent post. But you can eliminate the causes with a solid process of elimination.
*NOTE* that Noctua fan/cooler is still working in that system to this day. It was purchased with the first CORE i7 920 series in 2009(IIRC). Prior to that time I was not familiar with Noctua at all and have since had only good experiences with their products. So just wanted to be clear I was not implying anything negative about Noctua products.
I'm also using a Noctua, which is quiet and easily cools my 65w cpu.
The biggest clue is that my system seems rock solid when it does boot, and that my system was solid for about 9 months since building it. No hardware changes since that time. No overclocking, which is largely responsible for those CPUs that do fail.
I keep a couple of speakers I removed from old cases I junked just in case I ever need one. The last couple of cases I bought had a spot for a speaker but no actual speaker installed. Most motherboards these days come with a little speaker mounted right on the motherboard. About all its good for is making a beep sound, I wouldn't even really call it a speaker, more of a little buzzer.
It was either the motherboard or PSU. Gigabyte seems so sure that was not the motherboard. But Gigabyte will not ship my 1st motherboard back to me for unknown reasons. They shipped it once but the UPS driver must have tried to deliver to another address, where it got refused and sent back to Gigabyte. UNBELIEVABLE!!!
Well, did they actually recieve the 1st board back? I'd be on them like horseflies on poop to send it back. I mean they'd expect several calls a day.
I dealt with them once, they don't stand behimd their product and they get jittery if it even sounds like it's their product. That's why I switched to Asus almost 10 years ago, they've always done me well. MSI was good too, they actually sent me a couple of new "Mboxes" when the ones I bought failed within the warranty period. Those were a line of halfway decent Barebones systems they used to make, they came with InWin cases, I still have the cases, they are not made out of cheap pot-metal, but brushed aluminum.
Sounds pretty infuriating, if they won't comply, I'd try to find an arbitrator.