USB Add-On Card Speed Drops to All or Just One Port

[ParatoOptimal]

When using a USB2.0/Firewire Combo Add-On Card or just a USB2.0 Add-On Card does connecting a USB1.1 device to one of the ports reduce all ports on the card to USB1.1 or just the one that the USB1.1 device is connected to?

I'd like to be able to connect my USB1.1 Keyboard and Moust AND still use the other ports at USB2.0 speeds for other USB2.0 hubs/devices?

Thanks