I have recently upgraded my DSL peed to 1.5 Mbps. When I tried to download something I have noticed that speed is around 520 Kbps. I connected computer directly to internet and speed was as it should be. After this I tried to connect to internet with laptop and wireless through router and speed was down again. If connected directly to internet then the laptop also have designed speed. What might be the problem here?
You . clearly. Have a problem with the router. Buy doing this troubleshooting you described you have dismissed possible network card, cable and wireless card problems. Only thing that is left is router. You can try to update its firmware but I suggest you to send router back to store where you have bought it and ask for working one.