Quick hit here, I installed Red Hat Enterprise Linux 7 on a decent, but old laptop to let me play with OpenStack in a semi portable way. The only issue is that I want to close the lid and leave it running and still be able to attach to it. Close the lid, power savings kick in. To stop that, just edit:
/etc/systemd/logind.conf
and change:
#HandleLidSwitch=suspend
to:
HandleLidSwitch=ignore