Actually, I guess newegg deactivated the one I was looking at. So the one I have listed here is an older one. But apparently it's the only P55, in the 200 dollar price range anyways that does x16 x16 for PCIe cards. But I don't get all the new bells and whistles. So what do you guys think? I read the review here that even if you go 8x 8x you would lose around 8% performance from your graphics cards. But is that worth all the cool things from the new motherboards? Just looking for some advice. Thanks a lot.
That board you listed doesn't do 16/16. Anyway, if you really want 16/16 go with a 1366 system. However, 16/8 is fine for most users. I'm not sure why you mention 8/8 since you wouldn't have to settle for that. Even if you did, yeah it would be like 8% performance loss IF you were crossfiring 5970s. In other words, much ado about nothing. Also, save a bunch of money going with Corsair 750TX, unless you just have to have modular.
The P55 boards run one card at x16, when you use 2 cards they run at x8/x8 as you stated. However, I thought the performance loss was about 4%, perhaps with the real expensive top card it raises a bit higher, but then, if you are XFiring 2 x 5970 you would not even notice the performance loss for many many years.
To put it in perspective, 30FPS is considered the playable framerate, so, in order for the performance loss tobe of any real consequence, it would mean XFire of 2 5970 cards at 16/16 giving you a Framerate of 32, so at 8/8 you would drop below the magic mark of 30. I mean really, can you imagine your XFire configeration giving you so low a framerate? If you still have your cards by the time that happens, the chances are running x8/x8 is the least of your issues
Debating on the Modular PSU or not. I have a HUGE case, Cooler Master Stacker 830, but it's awful for cable management. Haven't found anyone online as a good example with that case as well.
I haven't had any experience with cable management in that case, or come across any examples online. I know some cases can be a bear, but I just hate throwing $50 away on what is essentially a one-time convenience. That's $50 to upgrade some other part of the build. Heck, $50 is $40 short of a HAF 922.
Well, 3 recomendations for that motherboard sounds good to me. Thanks guys. Will see how easy it would be to maybe cut out some slots for cable management in my old case before I decide what route to go for the PSU.
Check out this heatsink: Scythe Mugen 2 $35 ($7.56 shipping) As it is a good at keeping temps down and being quiet.
If you're not planning to OC your GPU then I'd say that a good 650W PSU will be plenty for two 5850s. You can get good ones of those (and modular) for close to $100.