D-Link router question please

I have been using a Speedstream 5100 (5 lights) and a D-Link router
DI-614+ for a few years now receiving continuous data from early
morning till afternoon from my broker without any problems. I decided
to upgrade to a 802.11g style and purchased a DI-524 which works much
better with my wireless laptops. The problem that I am having when
using my main computer (ASUS P4PE lots of memery) is that every now and
again, at around 9:15 to 9:20 am est, the data stops. Checking the
routers Status > Device info. shows no WAN information. Switching the
modem and the router off and back on after few seconds, it
re-establishes the data flow and the WAN IP etc information is present.
It is using firmware version 3.02 and other than that, it works fine.
Am I overlooking any settings? Is there any way to check where the
problem exists when it happens next time? Many thanks for any help...