LGA 771 to 775 Adapter (MOD) – Run Cheap Xeon CPUs in a Core 2 Quad Motherboard


If you're looking to extend the life of your LGA 775 system, there's an adapter available now that will let you install faster (and usually cheaper) Intel Xeon processors (LGA 771) into a Core 2 Quad motherboard (LGA 775). These Xeons cost a lot less and are basically identical internally to the high-end Core 2 Quad CPUs.

List of LGA 771 & 775 CPUs + Current Prices

To make it easier to compare CPU prices and specifications, we made the pages shown below. The first link has all the LGA 771 and LGA 775 CPUs combined into 1 table (sorted by price), and the others are the original uncombined pages.

Where can I get an adapter?

Here's a current list of sellers (sorted by price). The sellers are located all over the world, so you should be able to find one that's close to you, and most of them will also ship worldwide.

Why would you want to do this?

Xeons are usually MUCH cheaper

For example, the Xeon E5450 is equivalent to a 3.0 GHz Core 2 Quad Q9650, and it currently costs about $32 (about $90 less than the Q9650).

Other good deals on LGA 771 Xeons include:

For detailed specs on all of the Xeons and a full list of current prices, take a look at this page.

Xeons also typically overclock better

Additionally, if you’re interested in overclocking (making the cpu go faster than its default speed), Xeon processors are usually made from the best silicon, so you can typically achieve higher overclocks with them.

Someone that recently did this mod successfully overclocked a Xeon X5470 from 3.33 GHz to 4.5 GHz on an ASUS P5Q PRO motherboard, so you can achieve really good results with these Xeons.

How does the adapter work?

The adapter is basically an electronic circuit on a sticker, and you place it on the Xeon processor (as shown in the picture below). This switches two of the pads on the bottom of the Xeon to make it compatible with a Core 2 Quad motherboard.

Xeons that are compatible with this adapter

This adapter is only compatible with LGA 771 Xeon processors. If you're unsure what LGA 771 means, it's the name of the CPU socket used in some Xeon motherboards. And in comparison, LGA 775 is the name of the socket used in Core 2 Duo/Quad motherboards.

LGA 771 to 775 Adapter

Minor modification to the LGA 775 socket is also required

If you look at the LGA 775 socket in the picture below, you'll notice two tabs are circled in red. These tabs are there to stop you from installing a non-LGA 775 processor, and they'll need to be fully removed before you can install an LGA 771 cpu.

The tabs are pretty easy to remove if you have a sharp utility knife or box cutter (just be careful not to damage or bend any of the socket pins near the tabs).

Important: Make sure that you fully cut off each of these tabs. If they're not fully cut off, the processor may not align or seat correctly in the socket, which will stop it from making contact with all of the pins. If this happens, your system will likely fail to boot.

Once the tabs are cut off, you can use tweezers to safely remove the pieces from the socket.

The socket will then support LGA 771 or 775 processors (you can still reinstall your old processor if you ever need to).

Tabs to removed from the LGA 775 socket


Leave a reply
  1. Derek

    I’m interested in doing this mod, but would you need ECC ram to make it work since its a xeon?

    • syn Moderator

      Hi, since the memory controller is built into the motherboard with LGA 775, you just use the regular memory that the motherboard supports.

  2. Alex

    I plan to fit a e5450 in my old ASUS P5E-VM DO, do you think it’ll work? Or should I go for the tested e5410? Shouldn’t e5450 also work?

    • syn Moderator

      If an E5410 worked, an E5450 should also work (they’re both the same internally). In fact, any Xeon will probably work, since the motherboard supports ≥ 130 W TDP.

  3. Mark Owens

    Hello all. It’s been a while since I last posted something on this thread but I just thought I should say that there’s an authorized refurbisher on eBay who is selling Dell Optiplex 755s with Xeon X3363 CPUs installed. I’ve seen others sell Dell Optiplex 330s and 360s with Xeon E5450 CPUs installed. It just goes to show that this mod is legit and it appears that some of us–with the expert advice from Donnie and others–have been the trailblazers. In hindsight, I find it a bit humorous that up to recently, some on the Dell forums insisted that this mod could not and should not be done LOL!

  4. Len

    Hi Donnie,

    I tried to open AFUWIN stored in the files. Once I got by the permission issues I have found the app is old and not 64 bit. I downloaded a recent copy of AFUWIN 64 and am able to get to the start window of the application. I didn’t go any farther since I had some questions as how to proceed. I am able to view my saved file from the MMTOOL. The 1 old micro code I deleted is still gone and the 2 new micro codes I added from your listing are present. If you could give me a run thru as to what to expect to flash this file using AFUWIN would be appreciated.

    Thanks , Len

    • syn Moderator

      Hey, Len. Every flashing program is different, but if you just run the program, it should walk you through what to do.

  5. Maykon Helver

    tested and working on ASUS mother board.
    model: P5G41T-M LX3
    processor: INTEL XEON X5460
    Maximum speed fsb: 1600Mhz ( Overclock )
    chipset: INTEL G41

    was not necessary to modify the Bios, just update to latest version.

    testado e funcionando na placa mãe ASUS.
    modeol: P5G41T-M LX3
    processador: INTEL XEON X5460
    Maxima velocidade FSB : 1600Mhz ( Overclock )
    chipset: INTEL G41

    não foi necessário modificar a Bios, basta atualizar pra versão mais atual.

  6. Herbert Satos

    Hello, my Xeon X5460 processor running at just this 2.53Mhz (9.5x 266.64Mhz / FSB1066.56Mhz) what do I have 3.16Mhz of manufactures? (Already tried all options mentioned here)

    Motherboard: Asus PS5D2-VM (Chipset: SiS 671 and 968) (Bios: 0515 until today the most current) (this motherboard has no option to overclock)

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