Help with options (new case or sound card?)

Hello,
my situation toches on many areas so I hope I'm posting in the right forum.

I have an Antec mini case, mobo is Gigabyte ga-x58a-ud3r, 2 GTX 460 SLI.

Here is my issue. Mobo has 2 PCIe x16, 2 PCIe x8, 1 PCI.
I bought a PCI sound card, but one of the GTX 460 cards is blocking the PCI slot. I read how minimal of an impact running x16/x8 is, so I wanted to move one of the GTX cards to the available x8 slot (nearest the PSU). However, it doesn't fit.

My question:
- Should I return the PCI sound for a PCIe sound card (room in my current setup in the x8 slot)
- Should I get a bigger (mid) case? This will only be beneficial if the PSU position moves far enough down the case to allow me to connect one of the GTX 460 cards into the x8 slot.

In my current setup, the SLI config is blocking one of the PCIe X8 and PCI slot.

I have one PCIe x1 slot available, but any sound card would have to be small (is it called low profile) to fit because of components in the way.

I'm also not sure if a PCIe sound card is even recommended (not as good sound as PCI?)

Thanks for helping my complex situation. Please disregard the fact that the mobo has onboard sound.

Thanks
Dave