Hi guys N gals, I have a strange PC problem I'd like to share and hear some opinions on. I recently upgraded the wife's PC to SSD, I also upgraded the case as the old one was a dust magnet, was forever cleaning the CPU & GPU coolers. So, after doing the change over and adding the SSD I did the usual reinstall of Windows 7 Ultimate 64, and all her software, But she started to get staggering in Sim3. This was not a problem before the upgrades. After some debate I decided the Asus GTX560Ti 1Gb was at fault, so a new gigabyte GTX760 2Gb was purchased. Now, here's where it gets weird, I did the normal switching off of PSU etc, even grounded my hand on the case, removed the 560 slotted the 760 in, had to change from mini HDMI to standard HDMI cable, no biggie. Cranked the PC expecting it to boot in the normal manner, but alas, for some weird reason it hangs during POST and beeps every 5secs, the board shows either 29 or S9 in the L.E.D readout, Ive checked the fault codes in the manual but the numbers I'm getting aren't listed, no help on Gigabyte's website either. Looked at BIOS updates but the BIOS is current. Mobo is a Gigabyte X77Z-UDH3 1155, i7 3770CPU, 8gig 1600Mhz ram, Corsair TX750 PSU. Strange thing is if I put the 560 back in it boots, no problems at all. I have even taken my GTX770 and tried that to eliminate the 760 being faulty out the box, but same problem, just hangs and beeps. This has got me baffled, Ive been building PC's for 15yrs and never had anything like this before, Ive investigated the bios and reset it to defaults with no change in boot up behavior, have even set the "initial graphics first" to PCI slot, so the PC will go straight to the PCI slot at boot, but no change. I have a spare Mobo, but would rather forgo having to install it and format a new PC again if at all possible. So, any ideas? all suggestions welcome.