EVGA 141 LGA 1366 Intel X58 ATX X58 SLI LE

The board is known primarily for its 3x SLI ability: http://www.tomshardware.com/forum/261616-30-asus-rampag...

That EVGA board is a very solid board and a very good competitor for the famous ASUS P6T...
EVGA also redesigned the chipset heatsink so that it doesnt block the aftermarket CPU coolers, which was a problem with the initial EVGA boards...

apparently the pci x8 is lock at x8, which equates to lower performance in SLI? is that correct?

and would that also mean i wouldnt be able to intall a x1 tv tuner card in the remaining x8 slot? im really confused on this one guys, any help would be greatly appreciated!

You wont notice any significant performance hit when running the cards in x16x8 config...

And as for whether you can use a PCIe x1 in a PCIe x8 slot, Yes you can...
http://en.wikipedia.org/wiki/PCI_Express