Having trouble with a PCIE slot and a UAD2 Quad

I am almost a week into what is shaping up to be the most frustrating computer build in my life. I've had terribly complex systems with Magma chassis, multiple UAD and Powercore cards, firewire  and PCI interfaces. I've seen just about everything but my current less is more system is turning out to be a total PITA.

Mobo is an Asus Z77 Pro Thunderbolt
i7 3770k processor
16 gigs of corsair ram
500 gig system drive
1TB RAID 1 for audio
PCI 1394 card with TI chipset for my interface.
650 watt corsair powersupply
H60 water cooler
Windows 7/64

It is my understanding that the i7 can handle the video demands of a DAW so everything on that list plus one UAD2 Quad would be rounding out the list.

After a myriad of little issues with trying to get things perfect with the install and the functionality of the audio driver for my Tascam DM3200/IF-FW audio interface I finally got things around to installing all my plugins including my UAD card. The card has been installed in my system that is being replaced for quite a while and working totally perfectly. 

The problem is that there seems to be some kind of connectivity issue with the card. Most of the time only one green light toward the bottom lights up when the system powers on but a few times all the lights have come on as expected and the card will become installed in the system. Most of the time only the one green light comes on and the LED on the bracket just flashes red over and over. 

There have been 4 occasions where the card has successfully powered up correctly. Once was just the system described above and the other times it was with a Radeon HD 4870 video card (because my eyes flashed some comment about i7 video causing some problems. I really don't want to use a video card if possible, especially a beast like the 4870 taking up two spaces and having yet another fan in the system.

The bracket on the UAD2 card is a little wonky and doesn't really have the best geometry when it's installed. I'm not sure if this is the problem or not. I've tried with and without a screw. Without a screw is too unstable. The card can move very easily and would be totally unsuitable for normal use without being mounted with a screw.

I'm at a loss. I think the card is compatible because I was able to launch and open plugins (although I couldn't play back without an audio interface connected). The whole thing is one big frustrating mystery like I haven't had in a long time. Ugh.

Any thoughts?

there seems to be some kind of connectivity issue with the card

An intermittent failure of the physical/electrical connection to the card is a real possibility. You can try a contact  cleaner on both the card plug and socket (thin blotter paper or cardboard to gently abrade the socket connectors) and careful inspection of the socket for foreign matter or a damaged contact. If there is a cold/fractured solder point from the board to the socket, there is not much you can do. Have you tried any other cards in the socket, or the problematic card in another socket if available? The fact that the card was previously working in another system speaks against a card problem.

What OS are you using? Since the LED seems to be an indicator that the driver is not communicating with the card, uninstalling and re-installing the software is a good idea. Rebooting may help. In order to provide the illusion of a fast boot,  windows 8 is designed not to do a full cold shut down and re-boot. It keeps the memory image of the last running kernel instance on the hard drive (sort of a modified hibernation state). If the driver is not loading properly on one boot, repeated power off and on (not by default a cold boot in Windows 8) may just re-create that unloaded state.

https://windowssecrets.com/newsletter/with-windows-8-off-isnt-really-off/

A power supply problem is very very unlikely to be the cause of the problem. 

Have you seen this?

http://www.uaudio.com/support/uad/troubleshooting/UAD2-LED-Key.html

If you are looking at a new motherboard, I've built two new systems in the last year.  One for my DAW and another for other uses.  My DAW is using a Gigabyte GAZ77X UD5H and an i7 3770.  I don't have a UAD, but everything else is working OK.   The second PC is using an ASRock Z77 Professional motherboard and an i5 CPU.  Both have UEFI BIOS'.  I'm thinking of swapping motherboards as the ASRock seems to have a faster SATA III controller (I can transfer data between two internal hard drives faster for one thing).

I don't use the fast boot, etc on either.

FWIW, I see a lot of problem posts with ASUS Motherboards on the computer forums I visit.  Whether its problems with ASUS or just that there are more ASUS boards in use?  I see a lot of problem posts with ASUS Xonar PC sound cards too.    

I have a going on 7 year old ASUS motherboard. Works fine. What I think I heard though about newer motherboards and computer is that the slots are shared. They seem not to be separate. Not sure what that means, but extra slots are PCI-3 1X slots (small). And most of the time, made for newer cards. Glad I use a USB audio interface. There is no room for bigger (deeper) cards and such. Ran into that problem even with my old computer and some video cards when having a audio card in the slot below. Now there is add-on wi-fi and whatever else also. Good luck, but heat would be a concern with anything like that also. That is just the way they make the newer motherboards now, so have to be aware of whatever it is they are coming out next. If there are newer short-profile (depth) cards, then or when they come out, then that is what you will have to use I guess. That is at least the way I understand it right now. I know my new computer (gateway) compared to my old computer is - cheaper made ( but it is a cheap computer anyway - my old one was not all that expensive either.) Those engineers keep changing things around, and well, the cards made for them - that is probably going to be a mystery for awhile also.