Best Motherboard for File Server (Max # of SATA-II connectors)

http://www.tyan.com/products/html/tempesti5000px.html
http://www.tyan.com/products/html/thunderk8hm.html 

This is the best I can currently find...
Gigabyte: GA-K8NXP-SLI
http://www.gigabyte.com.tw/Products/Motherboard/Products_Spec.aspx?ClassValue=Motherboard&ProductID=1859&ProductName=GA-K8NXP-SLI

8 x Serial ATA connector (4 X Serial ATA-II 3.0Gb/s, 4 x Serial ATA-I 1.5Gb/s)

That mobo is good.

And you are looking "...Trying to build a rack mount file server.."?

Why don't you just get your asus and add extra sata controllers, ot even a sata hardware raid controller with enough connectors? hardware raid should allways beat software raid...

rindi -> cost

I would rather have the SATA onboard rather then through a PCI bus.

Punky - The rack mount is just the type of case it is going into, I just wanted to ensure that a large format motherboard would be ok.

Then the mobo you found would be good. But consider the Rindi's recommend, that would be good suggestion as well. I read you worry about the cost, but the board you pick is also expensive, though.

The on-board SATA is almost certain to be on the PCI bus.  Look at an Asus board with PCI-X and go for an SAS card.  Max performance all the way around.  With the SAS you'll have the ability to run SATA or Serial Attached SCSI drives.  So, you can put your OS on a couple of SAS drives and RAID 'em, and put some whoppin' big SATA drives in for storage and RAID them too.  The best of all worlds in one package.

knoxzoo, some good ideas there.
Couple Questions, what is a sample product (please provide a link) and is this linux compatible?

Honestly I would love a hardware Raid 6 controller - just wondering about the compatibility/practicality - thus far I haven't found any products that fit the bill.

SAS is nice, as long as you can spend that much money:

Here's a "starting" point
http://www.mwave.com/mwave/viewspec.hmx?scriteria=3876346


I'd get a good ASUS mobo and a PCI-X card, this is less than 1/2 the cost, supports 8X500G and you can use a 2nd controllers to get to 8 TB:
http://www.mwave.com/mwave/viewspec.hmx?scriteria=3753460

I know it supports Redhat and Suse
http://www.promise.com/product/product_detail_eng.asp?segment=RAID%205%20HBAs&product_id=148

For the MOBO, any choice for the type of CPU (AMD/Intel) you want to use?

There happen to be many fool manufacturers around!

True, but I don't believe Adaptec is one of them.