Just so I understand right you play CSS just fine on the same laptop that lags out on DOD:S right?
The first thing I would try is disabling your wireless modem (right click My Computer, Manage, Device Manager on the left column, expand Network Adapters, right click on the wireless one and click disable). Then connect with an ethernet cable to see if you still get the timeout issue on DOD:S.
Also check and see if your wireless modem has the most up to date drivers. You can search the model name you find in the device manager to find the most recent update.