Not able to extend display to 3rd monitor

[boxboxbox]

GPU: Sapphire R9 280X Vapor-X Outputs: DVI-D, DVI-I, HDMI, DisplayPort
I have 3 Asus VN248H-P all with 2 HDMI and a VGA input, as well as an Asus PB298Q that has HDMI, DP and DVI-D.
This is how the 3 VN248's are connected

1. HDMI cable to HDMI output
2. VGA cable to VGA/DVI adapter to DVI-I output
3. VGA to HDMI cable to HDMI/DVI adapter to DVI-D output

I would prefer to run the PB298Q using a DP cable and the DP output, but that's besides the point.

I am running into the issue where you need to disconnect or replace one of the displays in order to get the 3rd display to extend. I can get all 3 monitors to power on and display my desktop independently, but when I try to run 3 the 3rd won't work. I've read a lot about similar issues being related to a passive adapter instead of an active one. I'm not using DisplayPort at the moment so I don't believe this to be the issue. Even with my 4th monitor plugged into DisplayPort it will work, but the 3rd of the VN248s will be grayed out and will not allow you to extend to that display. I've seen others have just gone with running one on HDMI, and the 2nd and 3rd running HDMI to DVI cables. If possible I'd rather not buy more cables if I can get this working with what I currently have.
I've tried what this poster suggested here http://www.tomshardware.com/forum/id-1908617/monitors-280x-working/page-2.html and have had no luck so far I'm still getting the "The Display Settings could not be saved. Please try a different combination of display settings."

 

[garryash]

Have you read the sticky "Eyefinity Setup Guide " at top of the "monitors" page on TOMS ???
I and a lot of others have this problem and the sticky tells you how to fix it !

 

[boxboxbox]

Have you read the sticky "Eyefinity Setup Guide " at top of the "monitors" page on TOMS ???
I and a lot of others have this problem and the sticky tells you how to fix it !

Yes I did read it over. According to Sapphire though I should not need to use the DisplayPort at all . I believe however though that the passive adapters (VGA/DVI, HDMI/DVI) are not allowing this to happen. If I didn't have any adapters in play and the cables were of the same port type as the input and output according to Sapphire it should work.

Now I understand due to the limitations of my Monitors (No DVI input) and my GPU (No VGA output) that I'm having to find a different solution.


I'm trying to buy the least amount of cables possible.

I've got two HDMI to DVI cables and a DisplayPort to HDMI active adapter in my amazon cart at the moment.

If I run HDMI to DVI on 2 of them and then run HDMI to the active DisplayPort adapter this should work with no issues correct? At that point I can then use the open HDMI output on the GPU to connect a 4th different monitor using just an HDMI cable?