Hello, I have a Toshiba Satellite P-750-BTG422 (1.5 years old now) and all at around the same time, I noticed several irritating issues which may or may not be related. Several days ago, my laptop's ethernet capabilities stopped working (recognizes the cable most of the time, but no network identification; ethernet to USB adapter functions fine), my laptop started getting unusually warm only in the bottom left corner where my ethernet cable is (regardless of whether it's plugged in or not), and now, even when I put the laptop into sleep mode (slowly blinking LED, no fan activity, black screen and all), that area remains warm (too warm), my battery life is drained far too quickly for sleep mode, and when I put my ear up against my laptop at the one spot, I hear this odd and faint whirring/whining noise.
My guess is the issues are connected and their is something faulty with my wireless/LAN adapter. I've tried restoring my system back to the earliest profile I have available, updating windows and my network-hardware drivers, tried automatic troubleshooting, tried messing around with my power mode settings, tried cleaning my fan, tried changing my network address in the adapter's properties menu, and I've tried resetting my TCP/IP. None of these nor any amount of reboots have done anything and I have no idea what could be the problem short of hardware failure (and I am past warranty). Any ideas? Thank you.
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The noise you hear is either the fan or the hard drive, that's probably normal. Although if the fan is not spinning and is trying to, that is bad.
Did you try a new network cable?
Sounds like you did pretty much everything to trouble-shoot the issue short of uninstalling and reinstalling Windows but that may not help you. Try a Linux Live CD to boot the laptop from, it won't require any formatting of the drive, just loads from the disk. You should be able to see if the issue is hardware (it won't work under Linux), or something with Windows (if it does work in Linux). Make sure the drivers for your net card are loaded under Linux, you don't want to have it not work, toss out the laptop and then realize that Linux simply did not have drivers for your model hehe.