Why can't my computer connect to wireless network?

I just bought a brand new desktop, a Lenovo K330 77274HU, and it includes a Realtek RTL8188CE wireless adapter to connect to my router. At first, the computer connected to the wireless network perfectly and I was able to browse the web. For some reason, the computer then began to disconnect from the wireless network and when it reconnected, internet access was unavailable. This disconnecting and reconnecting continued and still I was unable to access the internet. I have a laptop in the house that connects to the wireless network just fine and it has been for a year now. I downloaded a driver for the adapter and still, no dice. Any help to resolve this problem would be much appreciated.