Uh... You connect it the same way you would any computer:
1. Dial-up internet. You said you plugged in a phone line. Good. But the computer doesn't magically know how to dial anywhere. You need to go into the System Preferences or Internet Connect utilities to set it up. Obviously, you need to have a dial-up account with some company for this, and will need to know the phone number, user name, and password, at least.
2. High-speed internet. You also said you "tried many combinations using an extra DSL box..." Well, if it's extra, then it begs the question, WHY was it "extra"? DSL is a service that rides over the phone lines, but requires subscribing to it with an internet provider (often the phone company itself.) If you don't subscribe to DSL service, then having a DSL modem doesn't do you any good. Which brings us to: The phone line goes in the DSL modem, but you connect the DSL modem to the computer via an "Ethernet" cable. USUALLY, if you have an active DSL subscription, it should "just work", but some DSL providers make you go through hoops to set up the DSL modem. Finally, with regard to DSL, there can be only one single DSL modem on the phone line. If you have, say, a computer upstairs, and a computer downstairs, and you want both to be on the internet via DSL, you need a "router" to run one single DSL modem through. Two DSL modems on the same phone line won't work.
1. Dial-up internet. You said you plugged in a phone line. Good. But the computer doesn't magically know how to dial anywhere. You need to go into the System Preferences or Internet Connect utilities to set it up. Obviously, you need to have a dial-up account with some company for this, and will need to know the phone number, user name, and password, at least.
2. High-speed internet. You also said you "tried many combinations using an extra DSL box..." Well, if it's extra, then it begs the question, WHY was it "extra"? DSL is a service that rides over the phone lines, but requires subscribing to it with an internet provider (often the phone company itself.) If you don't subscribe to DSL service, then having a DSL modem doesn't do you any good. Which brings us to: The phone line goes in the DSL modem, but you connect the DSL modem to the computer via an "Ethernet" cable. USUALLY, if you have an active DSL subscription, it should "just work", but some DSL providers make you go through hoops to set up the DSL modem. Finally, with regard to DSL, there can be only one single DSL modem on the phone line. If you have, say, a computer upstairs, and a computer downstairs, and you want both to be on the internet via DSL, you need a "router" to run one single DSL modem through. Two DSL modems on the same phone line won't work.