Mobo assistance

Looking for a little advice on a mobo. I plan on OCing a q6600 with a 4850 GPU. Want the ability to upgrade and possibly/eventually crossfire. Can someone what the difference is btw these two boards and if it makes sense to save $10 by going with the first one below?

GIGABYTE GA-EP45-DS3R LGA 775 Intel P45 ATX Intel - Retail
http://www.newegg.com/Product/Prod [...] 6813128344

GIGABYTE GA-EP45-UD3P LGA 775 Intel P45 ATX Intel - Retail
http://www.newegg.com/Product/Prod [...] 6813128358

If you plan on going crossfire with a P45 board you will be running both cards at x8 instead of both at x16. Limits bandwidth on both cards. The P45 chipset has 16 lanes, and they are allocated as 16+0 or as 8+8. There's no way to get 16+8 from a total of 16. Motherboard manufacturers don't like to explain that properly, of course

That being said, the bottlenecks are not that serious with HD 4850 cards, especially at 1680x1050 or less.
http://www.legionhardware.com/document.php?id=761&p=8

Edit: the URL button is messed up. Now it pops up a box and I need to paste the URL there too. If I only paste it there the link is just shown but it's not a link. Does anybody test these upgrades to the Web site???

Edit: between those two motherboards: the UD3P has 8 SATA ports, the DS3R only 6. That's irrelevant to most people, of course. I do use 7 ports right now though, which means the DS3R wouldn't be good enough for me. I suggest you get the UD3P if you have a TV tuner in the PC - that's why I need so many hard disks.