are you saying that if the USB hub is disconnected the computer boots and then you can plug the hub back in and use it while the computer is running? Then if you try to re-boot with the hub still connected it will not boot?
If so that is actually a fairly common problem and the cure is simply to learn to unplug all your USB peripherals BEFORE booting.
Why some computers do this is anyone's guess but I would venture to say it is similar to the age old problem of some serial devices having to be shut down until after booting or a software fix to cause the specific port they are attached to to not be polled by the BIOS or but the OS during initiation.
A different hub bu a different manufacturer (or possibly even a different model by the same manufacturer) might also solve the problem should you care to try one.
Recently had connectivity issued with my old XP ended up changing to another XP listed below.
XP Professional
Version 2002 Service pack 3
Intel ®
Pentium ® 4 CPU 2.40 GHz
2.40 GHz, 512 MB of Ram
Got tower home, set it up, turned it on so I got the desktop screen plugged the USB Hub in the front USB port and the wifi card in the hub, good to go. I got on the internet fine. Later I turned it off and next day tried to start it again, nothing, nada just a cursor on a black screen.
I tried unplugging it from the power, doing reboot, nothing. Talked with someone who said take wifi card off and restart it, did that and still nothing. Figured I'd have to have this computer looked at also. Than I thought unplug the cord of the USB Hub and restart it. It started right up, plugged the wifi card in the back and we're good every time, but I can't plug the USB hub in the front USB port to use my thumb drives. I haven't tried the other one in the back and I don't want to it if possible. I'm wondering is it he HUB? It worked on the first one.
If I plug the Hub in then shut it off and later turn it on again, I always get a cursor on a black screen. Do you have ideas, thoughts on how to fix it? I've decided it's a hassle but if I have to I will just plug it in after I start it, and unplug it after I'm finished, but if you've had this happen and fixed it please let me know. Thanks.

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