And something else:

I had some issues with cooling. Try the following...
Open internet explorer and play some candy crush (or play video, ...). Put some load on the CPU so it heats up. If the fans do not kick in to cool it, cooling is set to passive. Having it on passive means that the system will halt to allow the system to cool down... This could be interpreted as 'freezing' :)

To change it I had to change the CsEnabled to 0, reboot and you will find it in the additional power options. After setting the cooling option to active you can change back by setting the option to 1 again (and reboot).

Reminder: setting it to 0 means no connected standby (and almost no battery drain), but disable bitlocker!

I have similar problems and found myself reinstalling windows numerous times. There were a few issues I had and freezing was one of them. What I did...

First: my config:
Dell Venue 11 pro i3 (MS, HW revision 00) with 3G mobile module, travel keyboard (battery) and stylus (version A01). SSD is a Liteon 128 GB (installed firmware update 2)

I have firmware A11 installed, which works better for my touch and stylus sensitivity. Also A01 firmware for touch.

Steps done:

• In the bios, reset to defaults...
  (if you changed settings there like I did...)
• Re-installed windows - from recovery USB-stick
• Disable Link Power Management for Intel Rapid Storage
  In the Performance tab, click disable if it is enabled. Power off and power on to activate it!
  Fixes some of the freezes
• For the display driver, set panel self refresh to ‘off’
  Fixes some ‘freezes’ in which the display is not updated, but the system continues running
• Apply all windows updates, including Win 8.1 upgrade
• Install Dell Client System Update & updated all drivers
• Installed O2 SD-card update
  Needed as the 'old' driver, as well as the windows default driver left me with corrupted SD's after sleep/hibernation (more on this later)

I also have bitlocker enabled for my C-drive (SSD)...

I have a problem with the power drain... up to 4%/hour on connected standby (WITH keyboard attached, without it would be about 6%). Therefor I enabled user initiated hibernation...

in an admin commandprompt check that hibernation is active (powercfg /a; hibernate should be available)
If it is not available use the following command to activate:

• In registry changed the hibernation disk size to 100%
  Default is 80% (decimal 80). Can be changed in registry under the following key:
  HKLM/System/CurrentControlSet/Control/Power
  Value for HiberFileSizePercentage = 64 hex (100 decimal)
  (80% should be ok, but I had some problems returning from hibernation and with 100% it ‘always’ works)
  Do NOT set the flag yet for CsEnabled to 0 as hinted in other posts (could be handy, but...)
• Create a shortcut (optionaly also on the start menu/as tile):
  REM suspend bitlocker as it interfers with hibernation
  manage-bde.exe -protectors -disable c:
  REM shutdown to hibernation
  shutdown -h

This way the system goes to near-zero battery usage, which I can activate when not planning to use the tablet for some time. In general I keep it in connected standby.

If you do not want connected standby (I used it some time!) change the registry key CsEnabled to 0 (zero) and reboot. You will get additional power options, but connected standby is not available. I also had to disable bitlocker completely as I had to enter the recovery key more than once...

I noticed a line was missing during post:

in an admin commandprompt check that hibernation is active (powercfg /a; hibernate should be available) If it is not available use the following command to activate:

The command to enable hibernate is: (admin CMD)

powercfg /h on

Also check the reports generated by the power config cmd... I like the battery report as it shows the battery status & system efficiency. The energy report can hint on problems and the sleepstudy shows how bad the connected standby is (regarding battery drain)...