Same problem with both the Dell Venue 8 Pro and Dell Venue 11 Pro - won't power on. I found holding power button for 20 seconds, release and press again will start the tablet. However we should not have to fool around starting these tablets. WHETHER IT
IS MICROSOFT OR DELL GET IT FIXED!!! IT OCCURS SEVERAL TIMES A DAY AND IS AN ON GOING NUISANCE!!!!
UPDATE 5/1/2014
In doing more studying of this problem I found that the tablets are not actually being Shutdown. The various options Dell has provided for Shutdown, Charms, Power Button, etc. either cause the tablet to Hibernate or Sleep (Suspend). True Shutdowns are
not being performed. Holding the Power Button apparently kills Hibernation allowing the tablet to restart. During a "Shutdown" if the spinning dots go about half a turn the tablet is either Hibernating or Sleeping. During a true "Shutdown" the spinning
dots go about 4 turns.
Like many 8.x users I have installed Classic Shell's Classic Start Menu. First to be sure to go the their web site (www.classicshell.net) and update your copy. There has been a problem with update
notifications. Once updated go to the settings, Main Menu tab and uncheck "Enable hybrid shutdown". You will now be able to perform a true "Shutdown" using Classic Start Menu's Shutdown.
If you want to determine if your tablet has been sleeping or hibernating you can use the code below to create a VBS script. I named mine Uptime.vbs When you run the script it will tell how long it has been since an actual Shutdown or cold boot was performed.
Uptime.vbs
Set objShell = CreateObject("Wscript.Shell")
Set WshNetwork = WScript.CreateObject("WScript.Network")
Dim objOS, dateLastBoot, nSystemUptime
Dim nDays, nHours, nMinutes
'
' Get the Windows Home Server OS object
'
For Each objOS in GetObject( _
"winmgmts:").InstancesOf ("Win32_OperatingSystem")
'
' Return the last boot up time and
' convert it to a Date object
'
dateLastBoot = ConvertToDate(objOS.LastBootUpTime)
'
' Calculate the number of minutes between then and now
'
nSystemUptime = DateDiff("n", dateLastBoot, Now)
'
' Convert the total minutes into hours, days, and minutes
'
nDays = Int(nSystemUptime / 1440)
nHours = Int (((nSystemUptime / 1440) - nDays) * 24)
nMinutes = nSystemUptime Mod 60
'
' Display the result
'
objShell.Popup "Last Boot: " & dateLastBoot & vbCrLf & vbCrLf & "Computer Uptime: " & _
nDays & " days and " & nHours & " hours and " & nMinutes & " minutes", _
AUTO_DISMISS, "Windows Uptime " & _
WshNetwork.ComputerName, OK_BUTTON
Next
'
' This function takes a datetime string and converts
' it to a real date and time object
'
Function ConvertToDate(strDate)
Dim strYear, strMonth, strDay
Dim strHour, strMinute, strSecond
strYear = Left(strDate, 4)
strMonth = Mid(strDate, 5, 2)
strDay = Mid(strDate, 7, 2)
strHour = Mid(strDate, 9, 2)
strMinute = Mid(strDate, 11, 2)
strSecond = Mid(strDate, 13, 2)
ConvertToDate = DateSerial(strYear, strMonth, strDay) & " " & _
TimeSerial(strHour, strMinute, strSecond)
End Function