LGA 771 to 775 Adapter (MOD) – Run faster 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

The pages shown below should help with comparing Xeon prices and specifications. 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 $25 (about $70 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. HS

    Does it work with older 775 Boards like Abit AW-8 Max and Chipset 955X ?

    (sorry my first commend, the same like this, was in the wrong part of your webside)

  2. mkrmn61

    msi g33m-fi ms-7357 fully supported intel xeon x5460 and which stepping compability on mobo please help

  3. James

    Can report that this mod works with the following:

    Xeon E5450 (E0 stepping) SLBBM
    Gigabyte EP45-UD3R Revision 1.0 (BIOS version F12)

    Xeon appears to work completely out of the box (after resetting BIOS) in Windows 7 and Linux Mint, using BIOS F3 (original BIOS that came with my board), and F12 (latest available). However Windows 10 won’t install or boot (CPU lacks compareexchange128) until the correct Xeon microcodes are added. Once the microcodes are added, everything works perfectly.

    Haven’t tried overclocking yet though

  4. PG

    Anyone tested this out yet?


  5. joerg

    Anyone tested the board: Abit I-N73v?
    FSB 1333 and Extreme Core are supported.

    I want to by the Xeon e5450.
    Please Help

  6. Andrzej

    Thank you very much for your website and in depth instructions. I just needed to replace microcode for my GA-G33-DS2R to get Xeon E5450 and after following your manual I could install Windows 10 without any issues. Computer is stable and runs very nice. This is my second mod, first one is not that good since first mobo have issues with Xeon during BIOS and I need to click “del” every time I boot computer, not to big problem…

    Again THANK YOU!

  7. Phaethon

    ASUS P5QL/EPU (rev 1.00G) works with Xeon E5440, Stepping E0 SLBBJ. BIOS version 0408.

  8. Lman

    First of all, a great site, thank you very much for all the information.

    I would like to share my experience with this great mod:

    – Intel DG41TY, works like a charm with the recommended Xeon E5430 (C0). I used the last available BIOS (0045), cut the socket, changed the CPU, reset the CMOS, and the board boots with no problem. All the functions work.

    – EVGA NF66, works with Xeon E5430 (C0). This time I left the socket intact, and used a Dremel tool to file the grooves in the CPU itself. I used the last available BIOS (P05), cut the socket, changed the CPU, reset the CMOS, and the board boots with no problem. All the functions work.

    I would just like to add, that for me it was easier to use a Dremel tool, and file the CPU and make the grooves, the socket cutting was harder to do. So as a suggestion, you could include a photo or two in your guide of this second option.



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Problem with this MOD? Please read the troubleshooting section before reporting a problem. If that doesn't help, please tell us all of the things you've already tried.

Unsure about compatibility? Please read the motherboard compatibility and tested motherboards sections of this guide.


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