P55 and USB3.0/SATA 3.0

[wolfpack15]

Quick question regarding P55 architecture and using the USB3.0/SATA3.0.

I have heard that on Gigabyte's motherboards, if you attempt to do crossfire/SLI, USB3.0/SATA3.0 will revert to 2.0 speed.

I'm looking at building a new system with i7-860 and HD5970. Will only one video card (dual core though) cause PCIe bus to lower speeds to x8 and revert USB3.0/SATA3.0 to 2.0? or will it run at x16 while also allowing me to use USB and SATA at 3.0?

I'm looking at building a new system soon and I'm not going to overclock it heavily. Just in moderation. Based on that, which MB would you recommend from below? If there are any better suggestions than those two, please let me know as well.

Gigabyte GA-P55A-UD3P
http://www.newegg.com/Product/Produc...-417-_-Product

OR

Asus
http://www.newegg.com/Product/Produc...82E16813131620


Thanks in advance.

 

[Jd007]

The Gigabyte board's second PCI-E slot will only run at 4x, so don't get it if you plan to CrossFire/SLI. Get the GA-P55A-UD4P instead.

Only one video card won't effect USB 3.0/SATA 6Gbps speeds so you will be fine.

 

[wolfpack15]

Thanks for the quick reply. Yeah I intend to go with only one video card (HD5970). It's been tough finding a website with that video card in stock. I will probably end up waiting anyway until the end of this month to see what nVidia comes up with. If I do go crossfire/SLI route, I will probably end up going with i7-920 instead of Lynnfield processor.

So just for clarification, HD5970 should be fine running at x16 with USB/SATA at 3.0 even though it's dual core (internal crossfire)?