Much difference between PCIE 16 and 8?

[scor81]

Hi Guys..

I have an SLI 670's in my PC. I've noticed something about my mobo (gigabyte z68 xp ud3)...

* The PCIEX16 slot operates at up to x8 mode when AMD CrossFireX™/NVIDIA SLI is enabled.

How much would this be affecting my performance in games? Do you think it's worth changing the mobo for this? and if so... which one is the best bang for buck at the moment?

I don't really like the mobo I have at the moment, as its blue and as my gpu's are 3 slot cards, I can't fit my sound card in. I was willing to live with this... but now I've just read the x8 PCIE thing, I may have to swap it out.

 

[akxpckwb]

Most motherboards do that. There are some cases where both lanes run at 16x tho.
Anyway the performance loss is minimal and is really not worth buying another motherboard. Try reading this http://www.tomshardware.com/reviews/pcie-geforce-gtx-480-x16-x8-x4,2696.html