Dual Dell 2007FP + 3007FP monitors result in 2007FP in permanent 'sleep mode'

Hi,

System:
Windows 10 64 bit
16 gb ram
AMD Ryzen 5 1500x quad core processor
dual Radeon RX 460 graphics cards
3 monitors (two HDMI, one DVI cable hookup)
     * Two DELL 2007 FP 20' (MX-OC9536-46634-6BB-41AS)
     * One DELL 3007 WFP 30'

Issue:
Since updating my Radeon RX 460 driver I cannot run all 3 monitors w/out one of them going into 'sleep mode' at startup and staying there permanently. It seems that I can only get two monitors to work on one of my video cards - I can switch the cables around to different monitors, two will always work on one of the video cards and one will be in sleep mode. When updating the graphics card drivers, all three monitors will actually be on temporarily during the update, but once the update is finished I once again have a monitor in sleep mode.

I have updated my BIOS as well. I have scoured the internet looking for a solution to this problem. I have also tried two DVI cables and one HDMI cable, as opposed to two HDMI cables and one DVI. Both combinations result in one monitor staying in sleep mode.

The 2007FP monitors were purchased directly from DELL back in 2006 - is it possible that these monitors are outdated for modern video cards? Any help on this issue is very much appreciated. I find this issue quite puzzling and have never seen this before when using these monitors. Please let me know if there is any additional information that would be helpful in troubleshooting this problem.

Thank you