I have a Windows 2008 server that needs to have the network card traffic capped at 1 or 2 megabits. Does anyone know if this can be accomplished by the Network card settings, registry trickery, or open-source/freeware applications?
This should be configured through GPO by applying a throttle rate to all source IP addresses associated to the card. See http://www.microsoft.com/downloads/details.aspx?FamilyID=59030735-8fde-47c7-aa96-d4108f779f20&displaylang=en for a detailed explanation.
You could do it at the user level through group policy -> Network -> Limit Reservable Bandwidth and tuning it up to X% [10mbs would yield 80% reserved, 100mbps would be 98%]. However, this is only per user, if you have a system that runs all of it's apps as something besides administrator, YMMV.
Generally, however, this is easier to do through your switch and traffic shaping tools. Or if you really just need a speed reduction, kick the port into half-duplex.
You might want to check out NetLimiter:
NetLimiter is an ultimate internet traffic control and monitoring tool designed for Windows. You can use NetLimiter to set download/upload transfer rate limits for applications or even single connection and monitor their internet traffic.
Vista/Server2008 does have a network throttling mechanism included that is used when there is multimedia playing on the computer. It's a registry setting.
If you can't throttle at the driver/switch level, you can probably utilize this as a workaround.