|I am currently using a USB modem (aircard) to connect to the internet via Alltel Wireless.|
Anywhere from 30 seconds to 30 minutes, the modem behaves as if I have physically disconnected/reconnected. What's odd, though, is that Device Manager shows no issues or conflicts during this time. It's as if the modem completely freezes.
I was having this problem previously on XP Pro x64 edition, but I just performed clean installs of Vista 64-bit and 32-bit and am having the same issues. I've gone through uninstalling/reinstalling drivers and software to no avail, USB Root Hubs are not turning off devices to save power, mobo and chipset are up to date, and I even purchased a new USB card thinking it had gone bad.
These are brand new cards (I have been through three, thinking the cards had gone bad). Every card does the same thing. My ISP refuses to be of any assistance at this point, and I'd like to be able to use my main PC instead of my laptop on a daily basis.
As I try and work through this moronic USB modem issue, I've come across some similar situations, most of which have ended up being IRQ conflicts between the USB Host Controllers and audio or video cards.
In particular, I'm looking at IRQ 18 on my machine:
18 NEC PCI to USB Open Host Controller
18 NVIDIA GeForce 7800GT
18 VIA USB Enhanced Host Controller
All IRQ's are being used up to 23 at the moment. Unfortunately, my BIOS only allows me access (PCI or Reserved) up to 15. Vista is not allowing me to rearrange IRQ assignments.
1) Is this IRQ possibly the source of my issues with a USB modem that constantly freezes?
2) How can I get the IRQ assignments changed through Vista?
I can post the other IRQ's as well, if necessary.
PC specs are as follows:
Asus A8N-E, non-SLI, BIOS Rev. 1013
AMD Athlon 64 X2 4800+
BFGTech GeForce 7800GT
two separate generic USB2.0 cards
Vista Ultimate 32-bit (although issue is similar on 64-bit Vista and 64-bit Windows XP Pro)
Thanks in advance.