As it turns out the G19 is not the only keyboard with a buit in USB hub.
The Microsoft/Razer Reclusa has a similiar design.
http://store.razerzone.com/store/razerusa/en_US/pd/productID.169414300/categoryId.35209000
I have been chasing this x58/ICH10 bug since May of last year when I received the Asus Rampage II Gene.
This problem is definitely more widespread than I think is discussed. Here's just one example of many threads that exist on the Asus forums about this problem:
http://vip.asus.com/forum/view.aspx?SLanguage=en-us&id=20100115022559953&board_id=1&model=Rampage%20...
It has spread to other tech forums as well:
http://techreport.com/forums/viewtopic.php?f=29&t=70751
This is really the kind of problem that leads people to look in the wrong direction. Couple in the apparent details that 32bit operating systems and systems without USB hubs - which I presume are a larger percentage of the market - are not impacted and this is an issue ripe for never being adequately addressed.
As I understand what was written here the G19 actually stops working as the system works up to the crash. The Reclusa meanwhile has exhibited a different set of behaviors. The behavior of this problem has also changed on the Rampage II Gene over the course of the BIOS releases.
The original and early BIOS releases had the problem manifest by crackling of audio, the onboard NIC fully disconnecting, and the CPU usage climbing up to 100% on a single core before finally hardlocking or ending in a BSOD that did not leave a crash dump. The later BIOS firmware - including the most recent 1202 - no longer disconnects the NIC or has the CPU usage of the first core climb to 100%, but it still has the crackling audio along with the eventual hardlock or BSOD.
LIke many others my self discovered solution was using the warm boot method. Discovering this method implied to me that this was some sort of firmware bug in the BIOS, but I wasn't sure which component was at fault. I believed - incorrectly - that it must have been the CPU power management or the motherboard poorly managing the voltage. The discovery of this thread has more clearly defined that the issue is with the bus and more specifically the USB bus.
I am still in the process of testing, but at this time it appears that disabling the EHCI Hand Off has been the silver bullet for my issues on the Asus Rampage II Gene. This certainly makes me leary to attach any further USB hubs to my system; i.e. monitor. It also made me feel a bit dumb to be honest. Leaving the EHCI Hand Off at the default of Enabled when the text description to the right said to cut it off? Not the finest hour for me or my reading skills.
Now with the information Logitech has provided I believe this has the potential to be a true hardware errata with the ICH10 or an issues with the Microsoft 64bit USB drivers. Logitech, as a vendor my expectation is that you have the ability to make the connections to these large corporations. A discussion with Intel might be a fruitful direction. Intel is in a position to track down the precise elements of this issue and determine what is or isn't at fault. If it is a hardware errata in their design they can release a specification update and push out a firmware fix to all the vendors. Once a firmware fix from Intel is released Logitech would be in a great position to push the motherboard makers to roll out that firmware fix to their customers.
If this is actually the fault of the 64bit USB drivers in Microsoft products then that fix needs to be spread to more than just Windows 7, which is a problem with the currently i790 patch listed in this thread; sort of hard to test it on Vista64 and determine its worth.
I really feel like this problem needs more attention. A good news article that details the situation in a concise and simple way I believe would generate a wellspring of people with the issue who were pulling their hair, confused as to the problem, or doing strange work arounds - like the warm boot method - just to use their machine. I also believe such an article would considerably assist Logitech in finally squashing this and removing this support headache. The G19 strikes me as the kind of profitable botique products that ends up in the hands of a vocal, loyal, and lucrative market. Getting slammed for something that isn't your fault is always frustrating.
