Conexant and SIS chipset issue?

[oD1Nz]

Well, this one has me stumped.

I built a computer for a client a while ago, using a Gigabyte SiS motherboard (http://tw.giga-byte.com/MotherBoard/Products/Products_GA-7S748.htm) with an Athlon 2500+ and 512 RAM (Leadtek MX440 GFX card). Got a phone call from him a few days ago, and asked for a modem to be put in - I said sure, and he dropped it off after work.

Had ordered a modem which came same day ( :D ), proceeded to put it in. Booted fine, but when it came to Windows, it loaded, got into his profile, loaded a few more programs, then just crashed and restarted itself. I knew it was working perfectly before so I took the modem out, and rebooted - worked fine. Thinking I had a dud modem, I ordered another one, which also had the same problem. Then, thinking I had a dud motherboard, I RMA'ed it through my supplier and got another one sent out (same model) - installed everything, booted, worked fine. Shut it down, put the modem in and boom, it starts restarting itself again.

Can anyone offer any suggestions as to why it's doing this? I've updated drivers, system is running SP1... everything else is fine. Perhaps should point out that both of the modems I tried were both based on Conexant chips. Anyone know if SiS Chipsets have issues with them?

Thanks guys.

[mird-OC]

Have you tried installing the latest SiS chipset drivers before inserting the modem? I know conexant based modems have some very specific IRQ routing requirements that often aren't satisfied by default drivers.

[oD1Nz]

I'm not sure what you mean there Mird, because anytime I bootup with the modem in, it'll just start on the restart pattern of doom... I have updated the SiS chipset drivers though, no difference.

Should I try installing the modem drivers before installing the modem? Also, I've noticed in the BIOS I can force an IRQ on the modem - any preference?

[mird-OC]

Yeah the problem is if you install the modem before installing the chipset drivers the routing is already set and won't update. This is just Windows being dumb. Usually when this happens you actually have to uninstall the modem drivers, uninstall the chipset drivers, shutdown, remove the modem, boot, install chipset drivers, shutdown, insert modem, boot, install modem drivers.

Often windows will still actually keep the routing for that device for whichever PCI slot you installed it in, so if you still have no luck try the above procedure but reinstall the modem into a different slot.

This may or may not be a solution, but the advice I'm offering is from similar experiences I've had in the past with Conexant based modems.

You shouldn't need to force the IRQ and infact it's probably best you don't but if all else fails there's no harm in trying ;)

[oD1Nz]

Hmm... interesting.

Just booted into safemode as a last attempt with the modem in - windows pops up a window saying "Hardware installation is complete - restart?" before I could start doing anything. I restart and run normal XP, and... *YAY*... no restarting.

Thanks for your help anyway man :) :) :).

[PANiC_nz]

I had a similar problem with a Soltek Kt133A board and Conexant chipst based modem. I ended up throwing it out the window, and got a external US Robotics modem.