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 eBay 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 $12 on eBay (usually much 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

2,267 Responses

  • Jim January 22, 201811:11 am

    I’ve been looking for an answer to the following question and can’t seem to find it. Can I increase the ram beyond 4GB as long as I’m using a 64bit OS? Background, I’ve already performed the mod all seems to be working fine.

    • m4dc0r3 February 2, 20189:49 am

      Well it isn’t just the Os.
      The motherboard’s chipset must also support it and also cpu if I’m not mistaken.

  • Dika Putra January 24, 201811:31 pm

    First I want to thank you to this awesome web/blog this is very helpful!, just keep up the good work!,
    Second sorry about my poor english,
    and last I have questions:

    I have already update microchips to bios, with the last bios, but the instructions dont complete,
    the exist just (mmx, sse, sse2, sse3, ssse3 and EMT64).
    sse4.1 and VT-x is missing.
    The bios is AMI
    Mobo Biostar G41D3+

    Thank you for respon n attention,
    Keep up the good work!

  • Fazekas-Gyerman Robert January 26, 20185:06 pm

    Dell Optiplex 380 CPUs works with the following CPUs:


  • Anon ;s January 29, 20183:45 pm

    Confirmed working on DG41TY E5430 C0 stepping

  • Gungdezz February 6, 20188:53 am

    Will any of these processor work on g41t-am boards?

  • jacob28754 February 7, 20183:01 am

    does foxconn p35a work with a xeon E5430? will i need to update microcods?

    • Stepa February 12, 20182:25 am

      Just “P35A” without additional letters?
      Judging by the specification, the processor should work. But for stability, it’s better to update the microcode.

  • MidNight16 February 7, 20183:59 am

    Confirmed fully working with updated microcode:

    Motherboard: MSI P43-Neo (ms-7519)
    CPU: Intel Xeon E5420 E0 1067Ah

  • Gungdezz February 13, 20189:29 am

    G41t-am not working intel xeon e5440
    Only long beep and blank screen.

    • Stepa February 15, 201810:53 pm

      long beep – most likely the problem with the video card

      • Gungdezz February 15, 201810:57 pm

        So the videocard is not compatible with this processor?

        • Stepa February 15, 201811:22 pm

          I do not remember exactly, but “beep” means that a problem with the video card or RAM. It shall be written in a motherboard manual.

          Have you tried reset CMOS settings? If you have two memory modules try to remove one of them, will the motherboard start?

          • Gungdezz February 15, 201811:32 pm

            Tried switching ram,nope
            Tried 1 ram, nope
            Tried without videocard, nope
            Tried without ram and videocard, still nope!
            Tried old processor, it worked

            What is cmos?

          • Stepa February 15, 201811:59 pm

            The board must have a jumper to reset CMOS settings. But you can try to pull out the battery and after a while insert it.

    • Stepa February 16, 201812:10 am

      If nothing helps, try updating the BIOS of the motherboard. Perhaps you are using an older version that does not support 45nm processors.

      • Gungdezz February 16, 201812:24 am

        I have found 0 updates for this motherboard also my old processor is a 65nm doen this mean it will not support any 45nm processor?

        Will it not support processor like pentium dual core e5700?

        • Stepa February 16, 20188:53 am

          Can you check which BIOS version is installed?

          Perhaps you have a motherboard the same as in this computer (Acer G41T-AM Rev: 1.2):
          the latest bios version is P01.A4 (2012/03/26)

          • Gungdezz February 16, 20189:01 am

            Mine is a g41t-am rev 1.0 not 1.2 does it use same bios?

          • Gungdezz February 16, 20189:06 am

            Also i do not own a vm288
            I just picked up the motherboard for 3$

        • Stepa February 16, 201810:17 am

          These motherboards were sold as part of computers. Therefore, the BIOS should be searched by computer model. Different revisions of motherboards (rev1.0 and rev1.2) can be with different BIOS, therefore it is necessary to search for BIOS for revision 1.0

          I found a mention that the motherboard rev1.0 was used in the Packard Bell iXtreme (PT.U57-PV.U57).

  • mrgabo February 15, 20189:01 am

    Hi, I wanted to tell you that the Xeon e5420 works on the PEGATRON ipm41d3 motherboard works … the mod works …! as to help those who want to try it look in YouTube tutorials on that specific card there are many in Portuguese … I hope this helps them

  • Rafael Costa Ferraz February 15, 201810:26 am

    Friends, thank you for the excellent website and for all the tips given here, plus I need a help, poor as I am I would like a certainty of which xeon has already been tested and confirmed for my motherboard.
    Striker Extreme (Nforce 680 Chipset)


    Thank you very much for your attention.

    • Stepa February 15, 201811:04 pm

      Worked: X5460, so the E5450 should also work

      Also for this board there is a modified BIOS:

      • Rafael Costa Ferraz February 16, 20187:20 am

        Hello friend, very grateful for your real help.
        the world needs more people like you who share information and really help people.
        I’m from Brazil and if all goes well I’ll be really happy.

        Friend, one more question, do you advise any of the 2? their price is practically the same ..
        Only the TDP has a considerable difference 80w-120w …..

        Another difference, without deepening …
        Which of the two models do I choose?
        SLBBM ?? SLANQ ??

        Thank you again

        • Stepa February 16, 201810:53 am

          I think it’s better to buy a processor with a smaller TDP. The best option is considered E5450.

          SLANQ – Core stepping C0 (CPUID 10676h)
          SLBBM – Core stepping E0 (CPUID 1067Ah)
          If possible, it is better to buy stepping E0 as it is newer.


Leave a Comment

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.