Dell uses a generic backplate with threaded studs (M3 probably) for LGA115# socket in your pc as well as older XPS/optiplex models that use intel 2nd through 9th gen cpus.  All the LGA115# socket mounting spacings are the same (75mm, also same as lga1200).    "The 4 holes for fastening the heatsink to the motherboard are placed in a square with a lateral length of 75 mm for Intel's sockets LGA 1156, LGA 1155, LGA 1150, LGA 1151 and LGA 1200. Cooling solutions should therefore be interchangeable." Many aftermarket cooler such as Noctua or Coolermaster usually use their own custom backplate, which means user needs to uninstall the Dell bakplate first.  However the Dell backplate is often epoxy glued to the backside of mobo making it hard or risky to remove.  For plug and play cooler upgrade from Dell generic pancake style cooler, you can consider Dell $50 LGA 1200 cooler for XPS 8940 (DP/N vwd01) or a similar cooler for Dell XPS8900/Workstation Tower 3620 (DP/N VWMTJ).  this cooler is rated to cover i7-10700k with TDP of 125W.  installation video: Dell XPS 8940 - The Easiest Cooling Upgrade, That You Need! - YouTube [IMAGE] VWMTJ [IMAGE] Dell backplate threaded stud (?M3)   [IMAGE] 3847 backplate But before you even consider upgrading from the Dell pancake cooler, you need to know that you can not overclock the 4790K in 3847 due to chipset.   TDP of 4790k is 88w only 4 w higher than 4790 and 4770.  you will run the 4790k at out of box frequency with some turbo.  I suggest you test cpu temp first using the stock pancake cooler and if temp is not high no need to bother upgrade unless you just want to do it anyway.
I have an Inspiron 3847 with the Dell-088DT1 motherboard running an i5-4460. I have upgraded to 16GB DDR3 and have an Nvidia GeForce GTX 750ti video card with 2GB memory. I would like to upgrade to an i7-4970k cpu for improved video editing performance and 4k playback. I've looked at a few cpu coolers and would like to know what cpu cooler would be recommended that would physically fit in my current system with the upgraded cpu if someone has done a similar upgrade.
i7 Upgrade cooler recommendaton