Full Firewire Port Failure (three different machines : iMac Intel, iMac G5, Black Macbook)

Question

I'm experiencing a failure of all FireWire ports on all of my three machines. I believe this problem began with a faulty external, FireWire powered hard drive from G-Tech. Here are all my specs, followed by a rundown of the order of events that has lead to this situation, followed by the various troubleshooting I have done.
Equipment :
iMac Aluminum Intel - 24" Mid 2007 - running OsX 10.5.8 - currently 1 FW400 and 1 FW800 ports disabled
iMac G5 - 20" - running OsX 10.5.8 - currently 2 FW400 ports disabled
MacBook - 13" black Early 2008 - running OsX 10.5.8 - currently 1 FW400 port disabled
2 500GB G-Drives (by G-Tech) - AC powered
1 5TB G-RAID Drive (by G-Tech) - AC powered
1 250GB G-Drive Mini (by G-Tech) - FW powered
Initial Setup :
1 500GB G-Drive connected directly to iMac Intel via FW800
1 500GB G-Drive connected to first 500GB G-Drive via FW800 (daisy chained)
1 250GB G-Drive connected to second 500GB G-Drive via FW400 (daisy chained)
1 5TB G-RAID connected directly to iMac Intel via FW800>400 adapter
Sequence of Events :
I had transferred some files to my G-Drive Mini in order to move them to my MacBook from my iMac Intel. I copied the files to the G-Drive Mini and ejected it normally and plugged it into my MacBook via FW400. The drive would not mount, and the power indication light would not go on. After experimenting with various connections and cables I was able to get the drive to power with FW400 and USB connected at the same time, but the drive would still not mount.
I then plugged the G-Drive Mini back into the 2nd 500GB G-Drive as it was previously connected via FW400. This action caused the G-Drive to immediately reboot and eject itself from my iMac Intel.
I then attempted to plug the G-Drive Mini into my older iMac G5 via FW400. Immediately upon plugging in, the computer shut down, and would not restart.
At this point I kind of started to freak out. I was unaware of the extent of the damage, but was upset that the FW powered G-Drive Mini had shutdown my iMac G5. I contacted G-Tech Support and they offered to replace the drive and instructed me how to manually reset the computer's SMC by opening up the iMac and finding the Cuda switch. This worked and the computer was able to start and function again, but the FW400 port seemed to be disabled.
I then tried to swap out configurations and drives on my iMac Intel to see if there was any cable problems, but doing so, slowly rendered all my FireWire ports useless. It's almost as if the act of plugging in the FW-powered G-Drive Mini started a kind of shortout chain reaction. I soon learned that none of my hard drives would connect to any of my three machines, with any kind of cable combination via FW400 or 800.
I am currently able to connect my 5TB G-RAID drive to any machine via USB, as well as my G-Drive Mini. I am unable to access the other two external hard drives, as one has only FW400 and 800 ports and the other's USB connection is not functional as well on any machine.
Troubleshooting Steps Taken :
I have on all machines, reset the SMC in the following methods. iMac G5 - manually, by opening the case and pressing Cuda switch. iMac Intel - unplug, hold power button, restart method. MacBook - unplug, hold power button, restart method.
I have also on all machines, reset the PRAM by the Cmnd + Opt + P + R method at startup.
I have also unplugged all cables / removed battery, from all machines and left alone for a period of at least 12 hours, then re-plugged in each device one at a time.
I have also restored my hibernate mode (through Terminal) on my iMac Intel to mode 3 and also turned on Virtual Memory in system preferences and set hibernatemode to mode 7, the restarted and attempted to plug in devices. The reason I even began to deal with the hibernate mode was because I had around the same time my ports began malfunctioning, installed the DeepSleep widget, which allows you to control your computer's hibernate mode. I thought that tweaking with this setting may have made my computer incapable of recognizing devices that were plugged in. I have since uninstalled the widget and experimented with different hibernatemodes to no avail.
I also have Repaired Disk Permissions and Repaired Disk on all my machines, from within my Admin User as well as from the OsX Install Disk.
Sometimes in my System Profiler (like right now for example on my iMac Intel) my computer is "Unable to list FireWire devices," but sometimes, no warning message comes up and it simply displays the appropriate Bus speed.
I also conducted a system restore using a backup from my 5TB G-Raid Drive via USB, to a date before these problems started, but my ports are still not working.
Summary :
I am looking at a situation where all my FW ports on all my computers appear to be disabled, and possibly also on my four external hard drives, with one possible USB port malfunction on one external drive. The only root of this seems to be a malfunctioning FW-powered external hard drive.
Is this possible? Has this happened to anyone else before? G-Tech assures me that it is impossible for my 250GB G-Drive Mini to draw enough power from a computer to permanently disable any ports, but I have tried all of the FW port problem troubleshooting steps and am at a loss.
I do not have AppleCare and would like to avoid bringing two iMacs, a MacBook and four hard drives to the Apple store and take my chances with the geniuses.
I would appreciate any help or advice you all have. Thanks for reading and for your support!

Answer 1

Ok. So if that was too confusing, I've re-labeled this post with letters for my hard drives and some mapping of the connectivity configurations I have attempted.
Equipment :
iMac Aluminum Intel - 24" Mid 2007 - running OsX 10.5.8 - currently 1 FW400 and 1 FW800 ports disabled
iMac G5 - 20" - running OsX 10.5.8 - currently 2 FW400 ports disabled
MacBook - 13" black Early 2008 - running OsX 10.5.8 - currently 1 FW400 port disabled
1 500GB G-Drive (by G-Tech) w/ no USB port - AC powered : A
1 500GB G-Drive (by G-Tech) w/ USB port - AC powered : B
1 5TB G-RAID Drive (by G-Tech) - AC powered : C
1 250GB G-Drive Mini (by G-Tech) - FW powered : D
Initial Setup :
C > FW400-800 adapter > iMac Intel
D > FW400 > A > FW800 > B > FW800 > iMac Intel
Sequence of Events :
D > FW400 > MacBook
I had transferred some files to my G-Drive Mini D in order to move them to my MacBook from my iMac Intel. I copied the files to the G-Drive Mini D and ejected it normally and plugged it into my MacBook via FW400. The drive would not mount, and the power indication light would not go on. After experimenting with various connections and cables I was able to get the drive to power with FW400 and USB connected at the same time, but the drive would still not mount.
D > FW400 > A > FW800 > B > FW800 > iMac Intel
I then plugged the G-Drive Mini D back into the 2nd 500GB G-Drive A as it was previously connected via FW400. This action caused the G-Drive to immediately reboot and eject itself from my iMac Intel.
D > FW400 > iMac G5
I then attempted to plug the G-Drive Mini into my older iMac G5 via FW400. Immediately upon plugging in, the computer shut down, and would not restart.
At this point I kind of started to freak out. I was unaware of the extent of the damage, but was upset that the FW powered G-Drive Mini D had shutdown my iMac G5. I contacted G-Tech Support and they offered to replace the drive and instructed me how to manually reset the computer's SMC by opening up the iMac and finding the Cuda switch. This worked and the computer was able to start and function again, but the FW400 port seemed to be disabled.
I then tried to swap out configurations and drives on my iMac Intel to see if there was any cable problems, but doing so, slowly rendered all my FireWire ports useless. It's almost as if the act of plugging in the FW-powered G-Drive Mini D started a kind of shortout chain reaction. I soon learned that none of my hard drives would connect to any of my three machines, with any kind of cable combination via FW400 or 800.
D > USB > AnyMachine
C > USB > AnyMachine
I am currently able to connect my 5TB G-RAID C drive to any machine via USB, as well as my G-Drive Mini D. I am unable to access the other two external hard drives, as one has only FW400 and 800 ports (A) and the other's USB connection is not functional as well on any machine (B).
Troubleshooting Steps Taken :
I have on all machines, reset the SMC in the following methods. iMac G5 - manually, by opening the case and pressing Cuda switch. iMac Intel - unplug, hold power button, restart method. MacBook - unplug, hold power button, restart method.
I have also on all machines, reset the PRAM by the Cmnd + Opt + P + R method at startup.
I have also unplugged all cables / removed battery, from all machines and left alone for a period of at least 12 hours, then re-plugged in each device one at a time.
I have also restored my hibernate mode (through Terminal) on my iMac Intel to mode 3 and also turned on Virtual Memory in system preferences and set hibernatemode to mode 7, the restarted and attempted to plug in devices. The reason I even began to deal with the hibernate mode was because I had around the same time my ports began malfunctioning, installed the DeepSleep widget, which allows you to control your computer's hibernate mode. I thought that tweaking with this setting may have made my computer incapable of recognizing devices that were plugged in. I have since uninstalled the widget and experimented with different hibernatemodes to no avail.
I also have Repaired Disk Permissions and Repaired Disk on all my machines, from within my Admin User as well as from the OsX Install Disk.
Sometimes in my System Profiler (like right now for example on my iMac Intel) my computer is "Unable to list FireWire devices," but sometimes, no warning message comes up and it simply displays the appropriate Bus speed.
I also conducted a system restore using a backup from my 5TB G-Raid Drive C via USB, to a date before these problems started, but my ports are still not working.
Summary :
I am looking at a situation where all my FW ports on all my computers appear to be disabled, and possibly also on my four external hard drives (A, B, C, D), with one possible USB port malfunction on one external drive (B). The only root of this seems to be a malfunctioning FW-powered external hard drive.
Is this possible? Has this happened to anyone else before? G-Tech assures me that it is impossible for my 250GB G-Drive Mini D to draw enough power from a computer to permanently disable any ports, but I have tried all of the FW port problem troubleshooting steps and am at a loss.
I do not have AppleCare and would like to avoid bringing two iMacs, a MacBook and four hard drives to the Apple store and take my chances with the geniuses.
I would appreciate any help or advice you all have. Thanks for reading and for your support!