Inexplicable Networking Problem

I have two Dell laptops (Inspiron 9300 and Latitude X1) that share the same wireless connection. Last night, the 9300 started loading webpages quite slowly. The X1 still loaded (and continues to load) webpages normally. I ran speed tests on both laptops through speakeasy, and both said the max download speed was ~1000kB/s, which is quite fast. Unfortunately, the 9300 continues to load webpages slowly. What makes this problem especially odd is that if I load the 9300 in safe mode with networking, the pages load at the normal speed. I tried using a CAT5 connection instead of wireless, but it didn't help. I've also updated my wireless nic drivers, run two spyware programs, and run antivirus, all to no avail. The problem occurs regardless of whether I use Firefox or Internet Explorer. Any ideas? Thanks.