This seems strange, as I just recently did a new Win 7 Pro x64 build with the DX58SO and the ASUS GTX660 TI-DC2-2GD5 card. I too am running the latest mbd. chipset drivers and the 5599 BIOS. I am also running the latest Nvidia drivers (ver. 310.70) on the card. I haven't touched the VBIOS; just running what it shipped with which is 80.04.4B.00.5A according to GPU-Z Currently I am not over-clocking it. I know this isn't a solution for you, but my setup is functioning properly.
Based on this, I tried my motherboard with a friend's GTX 660 TI - made by Gigabyte rather than MSI. This one WORKED.
So it doesn't seem to be a compatibility issue between the card's VBIOS. There is something about the MSI card that the motherboard does not get along with.
I'm going to go back to MSI with this info.
I have the same board with the exact same problem. Same model of MSI card. I have been unable to get it to post in the DX58SO. I have however been able to get the card to work in SLI mode with another mfg card, a PNY. So there is either something wrong with the motherboard's support for this card, or with MSI. According to the MSI forums, it is an issue with the DX58SO as it is a known problem board.
Why is it I can get the card to work in SLI as a slave, but I can not get the card to work alone. Rather frustrated that other cards do work and this one brand will not. Do we need a bios update to fix this?
If you're talking about the thread I think you are, I started that one the other day with the same problem. I haven't had any issues with the DX58SO, so if it's a 'problem board' it's from the manufacturer's point of view and not mine.
If this is just an incompatibility, then it is what it is. I'll either get a new card or a new motherboard. It might be time for a full computer upgrade, so I'll have to think about it a bit.
Thanks for the assistance.
I'm having the same problem with DX58SO, but using a HIS Radeon 7850. Same behavior, only works as a secondary gpu.