A few questions:
- is the signal strength is sufficient? That is the most important question.
- is it slow with the inbuilt wireless as well as the dongle (with the inbuilt wireless switched off)?
- the Wi-Fi access point may support the 2.4 and the 5 GHz band, the W7 laptop may be using the one, you may be using the other. Also the same network may be repeated on different repeaters, especially in a hotel or resort. So are you using the same 2.4 or 5 GHz band, on the same wireless access point or the same repeater? The answer is likely yes, but to be sure....
- have you looked in the task manager, your computer may be busy with other things?
- it may be helpful to see the result of "ipconfig /all" (Windows key and R, type cmd and in that window ipconfig /all) of both your pc and the W7 laptop. Look for differences in Subnet Mask, Default Gateway, DHCP server and DNS server (should all be the same) and the IPv4 Address (should be different, but only in that part of the address where the subnet mask shows zeros). If your TCPIP settings are set to automatic this will be the case
Hope we find something