p45 is new and will be awsome but I read when you use both pcie its reduced to x8
will that make a diference? i wana run 2 4850's

thanks

well it looks like it depends on which one you get. some of the boards ( and i am talking about both the x38 and the p45) dont specifiy if they are full 16x crossfire while some do specify that they are only 16x and 8x when crossfired. other than that the p45 seem to be able to hold more ram. i saw one that supported 16gb. where as the x38's some have support for both ddr2 and ddr3 ( the p45 only support ddr2).

The X38 is 16x for both while the P45 is 8x for both
as for if it makes a difference, on a single card the difference is like 1-3% but I'm not sure if that's also true for 2 card systems.

http://www.newegg.com/Product/Prod [...] 6813131298 <--- the lone DDR3 p45 board.

It also cost more than x38 though. Kind of pointless at that price.

As for crossfire, all x38 support crossfire at 16x in PCIE2.0(32x, if you will). Some p45 support crossfire at 8x, others do not support it.

You have to keep in mind, p45 is a mid range chipset meant to replace the aging p35(soon to be out of production), while x38 is meant to be a high end chipset. The cheapest p45 model(which does not support crossfire) is $99.99, while the cheapest x38 is $200.

P45 is impressive enough to overclock the same as x38 at half price. You guys are expecting too much from something so cheap.

The P45 will likely hold your system back in XFIRE for the X4850s.