scrypt mining rig suggestions i went to configmyrig.com and selected the options to hit something close to 5mh.
here is a screenshot:

http://s28.postimg.org/uayj19exp/Screen_Shot_2014_01_09_at_11_21_58_PM.png

i'll be scrypt mining at a multipool and the total that came up for the complete setup is about $5,000 seems like alot but let me know if you have any suggestions. What i'm wondering is how many PSU's would I will need and what kind is recommended? I'm thinking it would be a gold or platinum for the PSUs but i'm not sure how many and what kind would suit 6 Radeon R9 290x's. Also is the motherboard &amp; cpu selected good enough? I'll be using a milk carton for the rig instead of a case so i'll need to get a hold of a good one.
What i'm wondering is how many PSU's would I will need and what kind is recommended? 


I would recommend much higher PSU, at least 1000 Watt PSU for each two Radeon's R9 290x. This is based on some recommendations I found (here and here). I am 99.99% confident a single 750 Watt PSU will NOT be able to cover 6 GPUs of that power. 

I also think the motherboard you selected can only take 3 cards, you need to double check. Even with 3 slots the cards may not have enough room between the slots, so you will need to use extension cables. The CPU is actually overpowered, I would select a low-power one. CPU will not be used for mining. Memory is not used as well. You will be covered with a 2-4GB stick to run the OS processes.

No one seem to be bothered with a case. For that much price of a hardware you don't want much dust to come in. Or any morning coffee spilt on your expensive hardware... I would advice to buy a large, solid, enclosure with good ventilation. This would cost you around $200. But it will protect the hardware much better then a milk or vegi plastic case.

Just thoughts, I am NOT a professional electrical engineer.