Ok so we have a DELL power edge T320 running windows server 2012 R2 Hyper V with 3 virtual servers DC, File server, and a windows 7 machine. We are having a problem where whenever something is plugged into the same power source (outlet or ups) the DC and the File server CPU spike to 98-99% and local network is sluggish at best probably because the DC is running so high until the hyper V is rebooted. Obvious solution is to NOT plug anything else in but I'm trying to figure out WHY.....

Thanks for any help or knowledge

Sounds like something is confused as to what its ground is. My first suspicion is the UPS but it's also the low-hanging fruit. The power supply in the PowerEdge might be fritzing. Worst case is that you have a ground fault in the circuit, but that seems unlikely. Usually a ground fault manifests a problem when you have two devices on separate circuits attempting to communicate.

Thanks Eric, The UPS has been replaced with same issue. it is a redundant power supply in the power edge and each power supply are pugged into separate UPS.

I would get a qualified commercial electrician to check the circuit. It should take less than an hour to diagnose, although I have no idea what you'd be looking at for a repair bill. With the PE straddling two inputs, a problem in the source(s) could be manifesting as a difference in electrical potential. Those will cause all kinds of screwball behavior. A way to self-diagnose would be to unplug the network cable while this is going on and see if CPU usage stabilizes; my guess is that this is mostly manifesting as noise in the network connection. Another way to test would be to unplug one PE power supply and then try to plug something in the same UPS/outlet as the remaining supply. If the problem doesn't show up, then you likely have an external supply problem but it could still be something wrong inside the PE.

Thanks Eric I will give these a try and post my findings

Hi Houston303,

How about the issue now?

Regards,