AT&T Southeast → [Speed Problem] Speed degrades over time?

After 2-3 days of continuous operation my FA-Ultra connection speed begin a "slow decay". I routinely "SUSPEND" my client machines at the end of the day instead of shuting the OS down and powering off. The modem and router stay powered on indefinitely. What is the recommended or accepted interval for needing to power off and restart everything from the modem on down?

Current setup:

Westell C90-600030-06 modem set to bridge mode.
Netgear MR814 router set for PPoE to login to FA-Ultra
Clients:
Dell Latitude C600 (WinXP SP1)
Dell Optiplex GX240 (WinXP SP2)
HP JetDirect EX Plus print server
generic linux box (NASLite from serverelements.com)

Whenever I do a cold reboot of everything, the speeds go to 1250+/220+ which is pretty much max for the Ultra link. What is causing the "decay"?

Thanks in advance for any advice.

Rick in Raleigh

That almost sounds a little like the issue I just had but in my case the deterioration became quite rapid. I'm doing better now that I set the PPPoE authentication in the modem and set IP Passthough to the router. The router needs to be set for DHCP configuration for the Internet (WAN) settings.

It may be worth a try.

unless your modem is dropping sync and resyncing at a lower speed (which you should see at least in the logs), the problem is probably with the software on the PCs.

i have found in my experiences, most equipment likes/needs to be powercycled somewhere from once a month to every 3 months.