Modem
Unsure on the possibility, but I would try a test from a different computer with a different modem to the same ISP. See if you get a better to different outcome when attempting that same connection with different hardware. If you get the same effect, you will then know its your ISP which gives poor service. If you get better results then we can say its the hardware or drivers.
Drivers can make every difference in how a hardware device perfoms. I don't want to say your problem is driver related, but it can very well be the issue.
Unsure on the possibility, but I would try a test from a different computer with a different modem to the same ISP. See if you get a better to different outcome when attempting that same connection with different hardware. If you get the same effect, you will then know its your ISP which gives poor service. If you get better results then we can say its the hardware or drivers.
Drivers can make every difference in how a hardware device perfoms. I don't want to say your problem is driver related, but it can very well be the issue.