I think you do not have a router between your PC and DSL modem, right?
DSL modem will timeout if there is no activity. Once your PC goes into standby mode, DSL modem will timeout shortly. After you turn on the computer again, open internet explorer. This will trigger the DSL modem to try to connect. The connection should be back in a few minutes.
If you do not like it this way, you need to buy a rounter and put it between your PC and DSL modem. The router has a function to send some packet to the DSL modem every few seconds to prevent it from timeout.
Now, you can try to 去死 if you want to.