Video Card Problem (cant explain in subject)

[Nerdock]

Hello, and hopefully thanks in advance!

I have a small problem with my video card. By small I mean complicated.

I built my own computer, to 3 years later, have my Geforce 550Ti no longer be recognized by my monitor. What I mean by that is: I have a 42" Westinghouse LCD TV that I use as my computer monitor, no problems until now. It has an auto-detect system that will detect new physical input cables (if the machine is on) and will automatically switch modes from say, DVI to HDMI, if you plug a HDMI cable into it.

Short Version: I built a computer for a friend who wanted to use old parts AND new parts, I told him bad idea, use all new parts. I tried to use my computer to compensate, install windows, etc. I then came home to find that my computer which was running perfectly, was now not being registered by my Westinghouse. I plugged in my HDMI cable into the 550Ti, and then it would say "auto-detect enabled, detecting HDMI, switching to HDMI" a few moments of nothing on the screen then the message "no signal".

Another piece to the puzzle: The HD that we were using, was my old Western Digital 10k Raptor, no problems ever, until I plugged it into the new machine. Tried plugging it back into my old one to install Windows, went off without a hitch. Then BOOTMGR wouldn't install, good times.

I have thus far bought a: new motherboard, 2 new video cards (neither of which worked, and I had this same problem happen with both), and new monitor. And it STILL won't work. The new video card will not work with either the new monitor or the old monitor, I have tried both PCIE slots, all parts are brand new. Even a new SSD, which was in the computer before the problems.

I am currently typing this on the onboard video from my motherboard, which my TV and new monitor (ASUS below) have no problem detecting.

Specs:

Same Processor - Intel i5 3.1ghz
New mobo: MSI Z77A-G45
Video cards: (old) Geforce 550Ti, Geforce gtx 650, ASUS/MSI Geforce 650
SSD: Corsair neutron SSD GTX 120 GB. (OS) HD: Seagate 1.5 TB (storage)
Monitors: Westinghouse 42" LCD TV, ASUS VN247 LCD Monitor (also recognized MOBO video, but not Video card)
RAM: 8GB Corsair (again, no problems, even now)
PSU: cooler master 650W (more than enough power for this machine)
OS: Win 7 64bit (legal copy)

TL;DR: Everything works perfectly when using on-board video, but I can NOT get a video card to work on this computer for SOME reason, even with mostly BRAND new parts.

I definitely know a bit more than the average consumer, but am by NO means a computer expert. This is a REAL stumper and I have less than no idea, so ANY help would be greatly appreciated! ^_^

Thanks,

-Nerdock

 

[SnowyGamester]

This might be a dumb question, but have you tried changing the video outputs manually rather than relying on automatically switching to HDMI? It really should switch to HDMI as soon as it's plugged in but the settings may have gotten screwed up somewhere along the line. Also since that mobo is based on the Z77 chipset you should be able to output from onboard graphics at the same time as a dedicated GPU...does it behave normally when outputting from onboard when the 550ti is connected? Does the GPU show up under detected hardware?

 

[Nerdock]

No, good question, and yes I have tried switching manually, and even when I do manually switch inputs, it's already on HDMI, because of the auto-detect system. Second part: Yes, the onboard video behaves the same when video cards are connected or not, no the GPU does not show up under detected hardware.

Thanks!

 

[SnowyGamester]

Well I'm stumped. If you've tried different cards and different motherboards and still nothing it's difficult to say where the problem lies. Perhaps your PSU is conking out a bit and not giving enough power, maybe just through the six pin connector or something...but I dunno.