The Intel® Core™ i7-2xxx Desktop Processors use a chipset based on the Intel® 6 Series Chipsets, while the Intel® Core™ i5-3xxx Desktop Processors use a chipset based on the Intel® 7 Series Chipsets. These processors are backward and forward compatible with some notable exceptions.
Intel recommends that you check with the manufacturer of the desktop board you are using to see if it supports the processor you want to use. Once you know the desktop board model number you are using or are going to purchase, go to the appropriate support page on the manufacturer support page and it will usually list supported processors for your board.
If you are installing an Intel® Core™ i7-3xxx Processor into a desktop board based on the Intel® 6 Series Chipset you may need an updated BIOS, ME8 firmware, and drivers. Always check with your desktop board manufacturer for supported processors and the recommended update process. Be aware that some boards have been revised to include the necessary support for these processors and some haven't. Updating the BIOS on Intel® 6 Series Chipset Desktop Boards shows the update process for Intel® Desktop Boards based on the Intel® 6 Series Chipset that require updating.