Hey Sonak,
You are having an Intermittent connection with your Broadband. What you have to establish is whether the fault is within your property or your local exchange.
Follow these steps and if the fault is still present then contact your ISP. (TALK TALK)
1> Are you using a USB, Ethernet or Wireless connection?
(This is the cable that connects your pc/laptop to your router.)
If using a wired conenction (Usb, ethernet) then check the power management feature on "Device Manager".
Press the "Windows Key" and the "Pause Break" key at the same time, this should give you "System Properties".
You will then be presented by several tabs click on "Hardware" then click on "Device Manager". You will then see a list of devices, click on the plus sign which shows your router, highlight the device right click on it and then click "Properties", on the tab which says "Power Management" make sure there is NO tick on the "Allow the computer to turn off this device to save power". If there is then obviously untick it and clcik apply and close device manager down.
If you have a Wireless connection there will be a similar option on your wireless adapter.
Once you have ruled out it is not your hardware, then concentrate on; Microfilters- Swap for a new one. How many telephones sockets do you have in your property? Are you connecting your router to your master socket ? (The socket which your dsl signal is guaranteed at) Are you microfiltering every device that uses a telephone socket? i.e Fax machines, telephones, Sky and house alarm (if it plugs into your telephone socket!!) After you have checked all of these connect directly to your master socket. If the problem is still persistant contact Talk Talk as there will be a fault which they need to take care of!! Good Luck!