I currently have a system running with an Asus P5PE-VM MB.  I have a mix of IDE and SATA.  I currently have one PROMISE SATA300 TX4 PCI card in the system.  My system is currently full with 10 drives and so I need to add a second PROMISE SATA300 TX4 PCI to my system to add the last 2 drives.  Has there been any issues with this configuration?  Is there anything I need to look out for?

Should work fine, though there's a possibility that your disk slots could get re-arranged.  To be safe, first go to the Devices page and make a note of which hard drive serial number is assigned to each disk.  Then after you install the new PCI controller, go back to the Devices page and verify things are set up the same.  (If they're not, just reassign the devices appropriately.)

 

Reason for this is that ports are assigned by PCI ID, which is determined by the order in which devices are "discovered" on the PCI bus.  For a given h/w configuration, PCI ID's don't change, but when the h/w/configuration changes, the PCI ID's can change.

Ok, I thought that the re-order thing might happen.

Since this would give me a total of 14 possible drives in this configuration, I would assume that should I wish to upgrade to 4.0 in the future that I should be able to add the 2 extras with out issue?

I don't have quite as many drives as you do (6 - SATA, 2 - IDE), but I'm running 3.1-beta2 on a Asus P5PE-VM and two Promise SATA300 TX4 PCI cards with no problems.  I second Joe's recommendation of writing down the devices and drive serial numbers.  You'll find that unRAID (the Linux OS running underneath unRAID really) orders the drives (i.e., sdh1, sdh2, etc.) in a different manner than does Promise (which uses port #s).

Ok, I thought that the re-order thing might happen.

Since this would give me a total of 14 possible drives in this configuration, I would assume that should I wish to upgrade to 4.0 in the future that I should be able to add the 2 extras with out issue?

 

Correct.