[Emerald Log Disappeared]

If you uninstalled a SL viewer (LL, beta or 3rd party), it has a nasty habit of deleting your chat logs as part of the process.

If chat logs are important to you or your business, make a backup copy before performing an uninstall.

[Anormally low FPS]

Have you checked the laptop's power saving features?  The CPU and GPU clocks could be reduced in a power-saving mode and therefore reduce your fps.

Try disabling all power-saving features or set to "Maximum Performance" and see if the problem persists.