Wifi working perfectly on my phone, but a mess on my notebook.

I have a HTC One X and my notebook is a Samsung R720 running Windows 7 Ultimate SP1. The wifi has been working perfectly on both my phone and notebook for a year or so, and now I installed a bunch of updates on my notebook and I think that caused my problems. Now I have a DLink router, WPA protected WIFI network. It works great on my phone, but on my notebook it takes minutes to load pages,...