Is there such a thing as a plug in internal Modem?

Hi please excuse my lack of computer knowledge, we have 3 computers in our house side by side,all connected to the same modem, we also have a wireless router which my son purchased recently to play his ps3 online,yesterday we had a big thunderstorm and a huge flash of lightning above our house, power went of momentarily, and the internet went down, no lights on modem. my computer was saying I had a network cable disconnected, I rebooted the modem numerous times but still no broadband. I discconnected the router and had everything back to original, but still no internet,I rang my service provider who said their equipment showed a exchange problem, anyway I went to work and my son plugged his router back in and the other 2 computers suddenly had internet but mine still doesn't . Doea this mean that my internal modem is fried and if so is it possible to install a plug in internal modem. my computer is nearly 5 yo so take that into account, its a hp pavillion t840a, I'm running xp. Please don't tell me to get another computer as I recently upgraded my ram and graphics card

 

sorry, I think I need to update my comments, the modem is connected to a landline, if we plug our cables into modem, we have no internet, turn the router on and plug our cables into router and we have internet, except for one computer which says network cable unplugged, I have checked cable, changed cables but no luck

 

You would be looking for a network card, and yes you can look for an internal card and install it, or there is even some usb options out there.

 

OK, I understand that I will need to buy a network card for the computer that doesn't have internet anymore, but why ,when we unplug the working computers from the router and replug them directly into the modem the adsl light goes out and we have no internet, plug them back into the router and the adsl light comes back on and we have internet, the modem is plugged into the landline and the router is plugged into the modem, does any one know whats happening??

 

If you have a router behind your adsl modem it may be in pass through or bridge mode, so plugging in to it directly will not get you internet.
But by your description it does sound like you NIC (ethernet card) in your PC took at hit and fried.

 

Does your modem have connections for three computers???? Generally, you only get ONE IP address from the ISP, therefore I do not understand how you can plug more than one device into the modem. If you can connect more than one device into your "modem" then it is likely also a router.