IOMMU feedback Gigabyte and AMD

IOMMU feedback Gigabyte and AMD

[Kenneth]

HI, If I try and install Ubuntu 13.10 AMD/64,
On a Gigabyte ga-990fxa-ud7 Revision 3 Motherboard with FD bios,
I have to enable IOMMU in the bios and complete the install process,
With out enabling IOMMU I have no USB 2.0 port inputs, the default ports 
one would use for a usb keyboard and mouse,
after completing the Ubuntu 13.10 install I have to disable IOMMU in the 
bios and then add iommu=soft to the kernel commandline/GRUB boot loader,
With out adding iommu=soft cd/dvd drives are not seen after boot.
Here is a link to Arch linux forums with the same errors I had and stuff.
https://bbs.archlinux.org/viewtopic.php?pid=1319548

This is jest some feedback for you, maybe some one will see this and 
look into it, it's beyond my skill level.
Thank you ....