Okay first do you have any errors in the device manager if so provide the hardware IDs, follow the instructions in this page: [URL] Did you install this driver: [URL]
  My specs. Dell optiplex 380, windows 7-64 bit, intell duo core 2.8ghz Below is my issue (beating a dead horse). Hoping someone can walk me through to the solution I had installed on my computer Windows 7 32bit so I decided "Hey, I'm going to up my ram to max capacity and I wanted 64bit windows to run the ram"Once I installed windows everything went great except for the damn network drivers not being on my computer. So I looked up this issue and this has happened to other people HOWEVER other people have better luck than I do. so I did a few things that were suggested.Enter BIO mode diagnostics -no issuesRe install the Dell optipex broadcom_57xx network card driver - WOULD NOT FINISH THE INSTALLwent to start menu and searched for device manager- I deleted some, probably import thing, from a some advice that a "Dell-name" guy stated to do and I was still unable upload the driverI even tried to install a Dell driver program that would find any issues with the stupid dell drivers- nothing of use doesn't run correctly.It all gos back to the fact that my computer does not have some damn ethernet LAN or wireless device driver which is causing me not to be able to connect to the internet. The error is literally (You have no network card drivers or something like that)It's really annoying that going from 32 to 64bit I have to come on here (even though I love this site) and beg for someone to help me. I've never had any issues like this before. I have no idea what to do. Maybe uninstall windows and re install 64bit again. Please for the love of God someone help me. 
Went from Win 7 32bit to 64bit. No network car drivers? Tried everything I 
know. Different driver downloads, extracts. I'm lost