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 $10 (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

1,844 Responses

  • na7ane October 9, 20176:14 am

    hello there , I’m thinking about purchasing xeon x5450

    but I’m a little confused , it seems like it’s already modified to run on 775 socket so I don’t have to worry about adapters and such

    but I’m not sure if it’s really as good as q9650 or not , I tried to see if it’s as good or not but it seems like there are no deep comparison on the web

    p.s. I’m buying it for gaming , I’m not saying that I’ll never use it for other stuff , but I want to know what’s better for gaming and gives me better fps

    also I’m not going to oc it , probably .. as I have no experience in doing that + I’m not even sure if my mb can oc it or not

    • Alex2000 October 9, 201710:35 am

      What’s your motherboard? Xeon e5450 is better than x5450. e5450’s perfomace is equal to q9650. For better overclocking results you should buy e5450 with latest stepping E0 (SLBBM).
      Don’t forget to check compability with your motherboard.

      Also check xeon list here:

      • na7ane October 9, 20174:31 pm

        my motherboard is g41mt or something .. it’s not for gaming but that’s what I have .. and I’m almost sure I can’t overclock with this mb

        my budget is around 20 bucks , I’m planing to buy a used cpu .. anything above 20$ I can’t buy .. and as I can see this e5450 costs around 27.50$ so I don’t think I’ll be able to buy it

        so are you saying that the x5450 is bad , or won’t get me good framerates ?

        + is it better to just buy a c2q q6600 or q6700 .. than buying a x5450 ?

        and one final question. in my mb info in official Intel site they say that it works for nm45 .. so does that mean it won’t run a nm65 CPU ?

        • Stepa October 10, 201710:03 am

          What is your motherboard model? Intel G41 Chipset?
          Instead of the E5450, you can buy the E5440. The difference in performance is small, but the price is half as much. In any case, it will be better than the Q6600 / Q6700.

          • na7ane October 10, 20174:14 pm

            I really I’m new to this stuff .. I don’t know much about hardware and such .. so I’m not sure if this is what you’re asking for or not

            my motherboard model name is Intel g41mt-s2pt

            about chipsit .. i googled how to find it .. in device manager/system devices

            I found those 2 lines

            Intel chipset PCI express root port 2E31

            Intel chipset processor to I/o controller – 2E30

            does modified Xeon e5440/5450 work on my motherboard ?

            also I have another question .. what is SLBBM .. and .. SLANQ .. what should I buy ?

        • Stepa October 11, 20171:41 am

          So you have the motherboard Gigabyte GA-G41MT-S2PT? The Xeon e5440/e5450 should work on this motherboard.

          SLANQ/SLANS – C0 Stepping
          SLBBM/SLBBJ – E0 Stepping (newer, it is considered that the revision E0 is better for overclocking)

          • na7ane October 11, 20174:54 am

            yes it’s that model .. thank for the info

            so do I consider that it’s possible to over clock the CPU with this mb , or is it a bad idea ?

  • Alex2000 October 9, 201710:22 am

    I got some issues with my eg43m motherboard (acer aspire m3800/m3802). I know I need to disable c1e. But the option is missing in bios. Trying to find how to add that option.

    Some problems are:
    Installing/loading windows takes forever. It took me about 30 hours to install windows 10.
    Stuttering in games.

    To make windows work good again I need to open registry and change intelppm’s START value to 4 (it’s located in HKEY_LOCAL_MACHINE\SYSTEM\ControlSet\Services\Intelppm) then reboot.

    Does anyone know how to disable c1e in my bios?

    • Stepa October 16, 20179:11 am

      Have you flashed a modified bios?

  • Zé Bandido October 10, 201710:36 pm

    Ive added the xeon microcodes on Gigabyte G41M Combo 1.4.
    I used the Q6600 on 500W PSU.
    Then I installed the Xeon x5470 and first crashed on Windows 10 boot.
    Then after several tryouts, the mobo started to write the BIOS before booting to Windows.
    After the writing I access the BIOS and got a message on MIT saying “…overclocked reversed…”.

    Then I resetted the BIOS through CMOS battery and turn off the PC for several hours.

    After that Ive turn on with a Windows 10 bootable pen and it started installing a new Windows 10.
    It worked until it asked me to reboot the PC, which i did. After that it started to behave as told early.

    Can it be the PSU fault? The Xeon is recognized on post.

    Ps: on PC Health tab i get 76 degrees celcius.

    Is this a faulty microcode issue or else?

    Thank you

    • Zé Bandido October 18, 201712:24 pm

      Just to tell that my issue was related to my PSU.
      Bought a 700W PSU and watercooling and works fine!

  • Giorgi October 11, 20174:37 pm

    HI, I have problem with ASUS P5G41T-M LX3 , I have updated bios 503 with microcode edited and it worked with x5460, but I have update to e5450 and when bios posted it shows “” to unleash this cpus full power update bios” I have already update what should I do, please help me out guys :(

    • Stepa October 16, 20179:02 am

      Most likely in your BIOS there is a microcode for only one revision of processors (stepping E0).
      To fix the problem, just add the missing microcode.

  • benjamin sheriff October 12, 20179:18 am

    E5450 “CO” stepping is working on the MSI PLATINUM COMBO which ant listed on the compatibility section , please add it to the page list!

  • Ccvvzzfg October 13, 20179:58 am

    Ga-ep45-ds3lr xeon e5450 C0 worked.


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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.