You will have to ask DELL your question.
An upgrade processor must be socket, chipset, AND DELL BIOS compatible. Only Dell can provide this information. Then, you can select from the list of processors they support on their BIOS on their board.
And, that is only if your existing processor is not soldered to the motherboard. Yours is. So, no, it will not be compatible.
You may want to review this: Intel® Desktop Processor Upgrade Information