This is actually spread out across 4 rigs  (3X 6950 + 6X 5830), with 2 more rigs in transit

my hash rate went from 18 (8800GTS) when I started, to the current rate of 2500 with 1500 more currently in transit

just don't be like this guy that fried the video card in his iMac:

http://forum.bitcoin.org/index.php?topic=13211.0

do you mean mining on a mobile device?

they are all gone and won't be back, they sold out yesterday, followed by sell out at tigerdirect

They probably have 6990s in stock too

Do you have Applecare?

They don't ship to USA

It is if you can find it in stock for $150

Windows can only support 4 ATI GPUs.  I am not sure what the limit is with Nvidia, but that's the reason why you were able to get Windows to recognize 4+ Nvidia GPUs

I've run the numbers and it isn't worth it to buy 6990s compared to a cheaper video card.  Unless someone has limited space in their apt, and can only run 1 rig with all 6990s vs 2 rigs with all 5830s.  Unless you've found a cache of used 6990s for 50% off, I can't see why someone would build with 6990s?  Maybe my math is off

easiest way to test is to load windows onto a machine with 3-6990s.  I'm sure someone has a rig with 3-6990s that can verify this?

windows can only run 4 GPUs

I ordered a few 6990s a few weeks ago that are on back order.  Meanwhile, I've been building rigs with cheap 5830s.
At this point, I am wondering if I should just cancel all my backorders for 6990s because it's not a great $ to MH ratio.
Is anyone getting 6990s just because you have money to burn?  You want to play video games too?  You believe they will hold up better for resale later?
What are your reasons?