Hi dudes,
I'm here to bring good news.
I got the same card as you from an ebay seller (the blue one), with exactly the same GPU-z specifications...
first thing I did was modify the .inf driver and install it... (after disable the windows non-signed drivers protection...)
then I was stuck on a very similar situation than yours...
After 6 hours working on it, I THINK (i did some tests like play some games but nothing very heavy or that would cause instability to make sure that it worked, but seems that did work...) that the unlocked msi vbios from the kepler topic works... http://forum.techinferno.com/general-notebook-discussions/1847-nvidia-kepler-vbios-mods-overclocking-editions-modified-clocks-voltage-tweaks.html
I flashed the card with that and restarted, at the first time I got blue screen after I tried to access the nVidia Control Panel, so I restarted the system again and BAZINGA...
I will keep you guys updated if any problem shows up but lets hope it doesn't happen!
EDIT--------------------------
Oh, forgot to mention, dont know if it has something to do, but I also installed the motherboard unlocked BIOS from http://forum.techinferno.com/msi/1839-msi-g-series-unlocked-bios.html