Back in April I bought a Gigabyte GA-Z77-DS3H motherboard with which to build a new system. Parts other than the motherboard were:
-16 GB DDR3 RAM (G.Skill F3-10666CL9D-8GBRL, two 8 GB kits, which model is on this motherboard's Qualified Vendor List);
-Intel Core i5-3570K Ivy Bridge CPU;
-MSI Twin Frozr II OC GeForce 560 Ti video card (PCIe 2.0);
-Intel Series 520 120 GB SSD;
-Antec Neo Eco 520C (520W ATX power supply);
-NZXT Source 210 Elite case.
Resume from sleep didn't work from the start (apparently due to bad RAM, more on that below). About three weeks in, the motherboard died completely, so I had to RMA it.
I got the motherboard back last Monday and, as suggested in the package insert, assemebled the system on a piece of cardboard, independent of the system case. It worked fine, so I reinstalled everything in the case. As of today, it is once again having severe malfunctions.
It turned out that two of my four RAM sticks were defective; they would prevent proper sleep/resume function in any PC they were installed in. I learned that by installing them in an older PC that never had problems before. So I RMA'd the bad RAM and am now using just the two remaining sticks (8 GB total). So I think that solves the resume-from-sleep problems I was having before the RMA.
But even with the bad RAM eliminated, my GA-Z77-DS3H is still not working. This morning, I tried to wake it from "sleep" mode. It powered up briefly, not even long enough to display the POST screen, then shut off. Then it powered up again on its own, emitted a long string of short, fast, error beeps, then shut down. It will repeat this power on, error beeps, power off, cycle for as long as I allow. Eventually, it will get to POST and load Windows 7.
Once again, I exchanged the original power supply (Antec 520C) with another power supply (Corsair CX 430, 430W). I also removed the MSI video card so I could use built-in video, just in case the video card was somehow causing problems. But the system is doing the same things.
I did manage to get the system working long enough to install the latest BIOS, version F6, but this has made no difference in the problems.
I am utterly fed up with this piece of garbage motherboard. I suppose I might as well do another RMA, if Gigabyte will pay the shipping. Otherwise I want either a completely new motherboard, or my purchase money refunded. This whole experience has been extremely disappointing. I built the system two months ago, but have been able to use it for perhaps 3 weeks total. I have never had so many problems with a new system, or with one particular component.