Thanks for the reply but something must have happened to my initial post. There was a lot more information when I posted it.
Anyway, I know that the short beep signifies POST was successful, was just giving it as information that I am not getting any error beep codes.
My mobo is a Gigabyte GA-X58A-UD3R with an Intel I-7 950 CPU, 3x4GB Crucial DDR3 DIMMs, 64GB SSD as system disk with 1TB and 500MB Western Digital SATA hard drives. Graphics card is an MSI GTX 670.
When I posted I'd eliminated all possible causes for the lack of video signal, don't even get the BIOS screens so card isn't even working in standard VGA mode.
1. The GTX670 is new (originally had a GTX 580 which exhibited the same systems and I'd figured it had to be the card or the power supply).
2. Both with the GTX580 and the GTX 670, I'd tried a different graphics card (NVidia Quadro) and this gave a video signal, system booted successfully into Windows.
3. Tested the NVidia Quadro, the GTX670 and the GTX580 in all PCI-E slots. Only the NVidia Quadro gave a video signal at all (and in all 3 slots).
4. Cut my KVM out of the loop in case that was the issue and cabled directly to the monitor (and yes the monitor works).
5. Tried a number of DVI cables with all 3 graphics cards, none worked with the 670 or 580 but all cables worked with the Quadro.
6. Have cleared CMOS.
7. Cursing and swearing at the PC didn't resolve anything either but made me feel better.
8. Tried the GTX670 in another PC and it provides a video signal there and that system boots successfully (couldn't do this with the 580 as this needs an 8-pin and 6-pin PCI-E power connections).
All of this convinced me that the GTX580 was faulty and returned it under warranty. Bought the GTX670 with the refund and as can be seen I still had the problem so concluded that it had to be some odd problem with the PSU (although it had worked for the best part of 2 years).
Just before I saw the reply to my post I'd just finished installing the new PSU I bought and still no video signal. I haven't run through any of the above tests as yet but I doubt if they will give any different results so now I'm totally stumped as to what the problem could be.
Things get even odder. Put both the GTX670 and Quadro cards in my system. Still didn't get any video signal from the 670 on boot, but did with the Quadro. Checked BIOS and all seemed fine, booted into Windows and installed the 670 drivers - these installed fine. I'd checked device manager and the 670 was initially showing a problem but this disappeared after a reboot. Also, if I connect the monitor to the Quadro I get a proper Windows desktop, with all my desktop short cuts and the toolbar. When I plug the monitor into the 670 I am getting video but all that is displayed is the background, no desktop icons, no toolbar but I do get the right-click context menu and can select an item. Opened the NVidia Control Panel, nothing happened but when I switched the monitor back to the Quadro it was open there. Very confused now - just waiting for my anti-virus to update then I'll take the Quadro out.
I've now taken the Quadro out and rebooted. Presented with a black screen from the point I powered the system up until Windows boot had completed and showing the login screen. However, I need to move the mouse at this point to get the screen to display.
I can login and work without a problem but for some reason the GTX 670 does not operate in standard VGA mode and so displays no O/P until Windows has loaded the 670 device drivers.
So if anybody has any suggestions as to how I can kick the card into life, I'd be grateful.
It seems the problem may be the GTX 670 card and compatibility with the motherboard in some strange way. I've just connected the PC to my TV using the HDMI socket on the card and it works just fine - video from power on. Now what I can't understand is why this doesn't happen when I use the DVI socket but do get video when Windows loads the device driver. Add to that, if I use a different GPU I get video from power on.
Anybody have any ideas. I've thought about flashing a new BIOS version but am unsure as to what version to use. The Gigabyte BIOS tools report my motherboard as a Rev 1 board (but the board is clearly marked Rev 2) and the BIOS reports it is version FB but I can't see any such version on the Gigabyte site for either a Rev 1 or Rev 2 board (I was hoping that would help confirm that I do have a Rev 2 board).
Thanks for the link but I'd already been there and neither the BIOS version for a Rev 1 board nor a Rev 2 board list the version my BIOS lists (FB). Since posting I have found a complete list for the Rev 2 board and it lists an FB version, confirming what my board says. Unfortunately I can't flash with the BIOS QFlash tool as the latest BIOS is a 2MB bios and the current QFlash will only accept a 1MB bios.
That leaves me with the option of using the @BIOS utility but I've read a lot of reports that it leaves you with a dead motherboard, so not inclined to try that. The alternative is to try and create a bootable USB stick - the BIOS contains a BIOS flash executable but this has to be run in DOS mode. I was hoping to find out if booting my Windows 7 system into command prompt only mode would be a safe environment to run FLASHSPI.EXE.
In general I don't flash BIOS unless I have a problem that a new BIOS will fix. I don't know if it will fix my problem but I've run out of ideas as to what to do next.
and if you tried all the pcie slot with the same condition, it could be compatibility problem, but don't know it is due to vga or motherboard yet.
I'm tending toward the GPU. I've contacted Gigabyte and they've tested same model board against an NVidia 670 card and say it works fine with that - even included a screenshot of a BIOS page showing board model and BIOS version - both agree with what I have.
MSI Forum have until now claiming it was the board but now advising me to contact MSI support. My card worked out of the box in another system I have with no problems - just wouldn't work properly on the system I want to put it in. The MSI forum suggested flashing the VBIOS to a version they gave me. That didn't make any difference on the target PC but stopped working at all on the other system.
When I flashed it back to the original VBIOS, it worked on the other system but still the same symptoms on the target PC. Although, when I switched it back from the other system, I got a brief flash of the BIOS splash screen but that hasn't happened again.
Guess I'll just have to wait and see what MSI support has to say when I can get into their site.
Thanks for taking the time to look at it though Beryl - I appreciate your efforts.
I've decided that, after spending the best part of two weeks on this problem, I will return the card. MSI technical support are abysmal and don't seem to want to take ownership of the problem. They suggest I just use the DVI port or contact my reseller, despite the fact that it is the DVI port that has the issue and I've already told them that the reseller support has told me that they have a number of reports that this card has incompatibility issues with a variety of motherboards.
Compared to Gigabyte (my motherboard manufacturer) they responded to my query about it within a day having tested one of their 670 cards on my motherboard model and BIOS version and provided screenshots to demonstrate there were no issues. Just waiting to get confirmation that an OC version of their card also works with my motherboard. At which point the MSI card is going back and I'll order a Gigabyte replacement.
Thanks for taking an interest and all your suggestions. Much appreciated.