Yesterday I fixed a problem with my PC, a Fujitsu-Siemens Scaleo-P. I post here in case the information could be useful for someone else.
The Scaleo-P has an ethernet port, but not wireless support. I bought an USB wireless adapter, but it wasn’t working. When the warranty expired, I tested an internal PCI board, but I got the same problems: the signal was going up and down and there was no way to connect.
Checking the hardware I found that the power supply was a 350W, so I switched to a 500W one. The internal adapter now works without troubles.
Edit: The internal PCI board still had troubles, so I switched to an external USB adapter. It’s working with almost no problems.
Edit (2010): The USB adapter works fine until the CD tray is opening/closing. While the tray is moving, the signal drops to zero and it comes back when the tray stops. Maybe it wasn’t a power supply problem but a cables/connectors issue.
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