Hello, I got a T640 Server, the weird thing is when i first got it. It was ok the following didn't happen, but now for some reason, when windows shuts down the server it powers off (power button goes off) monitor screen goes blue. But the fans stay on and the blue indicator light is still lit holding down the power button does nothing. I then have to physically pull out the power cord to actually switch everything off. I can power up as normal via the power button. and  windows boots up as normal no unexpected shutdown warning or anything, Windows doesn't see anything wrong. Any ideas. All i did was fill the server with disks and upgraded the raid card of which i didn't have this problem. (like it decided it was friday and from now on i am making the fans stay on)I have reset everything to factory setting, pulled the psu in and out of the machine, reset the bios, cmos removed the battery even when i first got the system i upgrade all firmwares and drivers via lifecycle .. But still it refuses to power off properly. Any ideas. Its not a problem more of an annoyance.. as i have to look at the power button light to see if it completed the windows shutdown procedure. The power supply is a kit single 1100w power supply, could it be this?

Thanks for any advice or if need more info please ask. 

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