Topic: 5970 x2 and v3800 x2 in one box - GUIminer issues... (Read 1004 times)

I hope someone can point this newbe in the right direction to solve this issue...

I currently have two PC's for solo mining.  

Household server running Windows 2008 R2 64bit:
Dell Precision 380
8GB ram
Quad core P4 3.73Ghz
One ATI v3800
Bitcoin running in -server mode
GUIminer setup with:
 - ATI v3800 hashing 70 Mhash with "-v -w 128" flags
 - 2 of the 4 CPU's hashing 3Mhash (better than nothing)
This server has 3 PCI-e slots: x16, x4, and x1.  The v3800 is in the x16 slot.  The other two are empty.

Workstation running Win7 64bit:
Asus P6T6 Revolution WS
12GB ECC ram
i7 920 processor
GUIminer setup with:
 - 5970 x2 hashing 1300 Mhash with "-v -w 128" flags, fans @ 100%, temp ~70c, 750 clock.
 - v3800 x2 (here is where the problem is)
 - GUIminer is connecting back to the household server to bitcoin.

Every time I try to start the v3800's, it says "connecting" in GUIminer, after about 10sec, windows pops that says
 "poclbm.exe has stopped working".  The GUIminer window stays on "connecting" forever.  
Now, if I stop the 5970's, the v3800 will start up fine, but when I restart the 5970's, one or two of the four GPU's won't start up and
display the same symptom.  Device Manager doesn't show any problems with the video cards.  These are NOT dedicated mining rigs, so they
need to run windows for "work at home" instances...

Any ideas as to what the problem could be and how to solve it?

Also, since I'm new at this, and I'm running solo, if I run 1500 Mhashs 24/7, approximatley how long would it be before I might see some coinage?

Thanks for your help in advance!