Will XEON work in Dell Studio XPS 9100 ?

Unknown by Dell since we never tested them. These are all we validated =
HXGV2 Gulftown i7-990X, 3.46GHz, B1
F3VGJ GulfTown i7-980X, 3.33GHz, 12MB, B1
152W9 GulfTown i7-970, 3.20GHz, 12MB, B1
MNWGW Bloomfield i7-960, 3.20GHz, 8MB, D0
VRDMW Bloomfield i7-930, 2.80GHz, 8MB, D0
G442M Bloomfield i7-920, 2.66GHz, 8MB, C0
1GKT0 Bloomfield i7-920, 2.66GHz, 8MB, D0

Yes it does support at least some Xeon processors. I am running X5675, its a 6-core 3.07Ghz 12MB ram, B1 stepping in it. Really cheap upgrade to boost performance if you are running a slower 4core i7.

They are one sale for like 140 at newegg currently.

I found this from Google. I know this is a rather old post but I registered to share with everyone my own experience. I hope others looking to do the same will find this information useful.

I too have a Dell XPS 9100 machine. It has the 5ND3X motherboard (revision A00). I upgraded to the A04 BIOS and replaced my stock Core i7 920 processor with the Xeon X5670 (SLBV7). The Xeon X5670 is only $120 USD as of June 2016 on Amazon.

Going from the 2.66GHz Core i7 920 to the 2.93GHz Xeon X5670 gave me a nice boost in single thread performance. From four core to six cores helped my multi-thread applications tremendously.

I'm user of Adobe Premier and have multiple virtual machines. I think this is a very inexpensive but super effective upgrade. I have a brand new Core i7 6700 machine as well. With this upgrade, my six years old Dell XPS 9100 now feels just as fast as the new computer in most of the applications I use.