HP destroyed a laptop for me trying to fix this issue. I found the usual BIOS by Insyde is the culprit and HP has, as far as I know continued to use it despite the defect.
In other words, no fix is available over a year later.
Bob
I have an HP 4310f desktop running Win7 Home Premium.
There are 6 rear/2 front usb ports. Rear ports are filled, front ones empty. Usb hub is connected to a rear port
.
I am using a nextag powered usb hub with 8 ports, 3 occupied. If the hub is connected, Win 7 will not start up. If I disconnect the hub, system continues and starts normally (do not have to power down/up again). Then I can reconnect the hub and proceed normally.
This is not a significant problem; I just have to ensure that hub is disconnected before turning system on.
However, out of interest I would like to get some input on this. Perhaps I am exceeding the 8 ports motherboard is designed to handle. Or possibly one of the other peripherals is causing the 'problem', although they operate when connected individually.

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