Forget boosting your internal WiFi. Go get some WiFi client (there are hundreds out there so I'll share an example) and try this.
For example.
1. Setup a TL-WR702N and wire it to your PC.
2. It's noted at http://www.tp-link.us/faq-395.html
Place the 702 closer to the WiFi hotspot. You can run 100 meters of Ethernet to your PC so that's an effective 100 meters range extension.
Cost? 20 or so bucks.
Hi, the problem I have is that I need to boost the wireless connectivity into my computer but I can't upgrade the wireless modem. In the office building I work at, a tenant in the upstairs office has allowed me to use his wireless internet and I have decent connections (half of five bars) sometimes and other times I can't even get a webpage to open. His connection upstairs is fine and works great. Now I don't want to upgrade his modem, so how can I improve the connection coming into my computer? It has a built in antenna.
Any help will be appreciated, thanks

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