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 $6 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

2,484 Responses

  • irytin May 23, 20209:55 am

    Hi. my motherboard is ipm41-d3 pegatron and i want install xeon e5440: how can i do that?

    • chantilly June 20, 20202:59 am

      i have installed a x5460 in this motherboard, runs great! Do you want to install?

  • ThreadStripper May 27, 202011:24 am

    I have a X3323 laying around, so I replaced a E7500 with it. The board is an ASUS P5G41-M LX. Everything seems to work fine except one thing, the BIOS keep saying ‘To unleash this CPU’s full power, please perform BIS update process.’ even if the BIOS is already the newest version. It also runs pretty hot, approaching 100°C when folding with Pentium D cooler (The multiplier has a pretty narrow range so it may be the issue, or it could be wrong temp readings, I have yet to tinkle with the BIOS).

    • Bekim June 10, 20207:06 pm

      I just upgraded my cpu from pentiom to core 2 quad and i had trouble with temp’s, so you need to change the cooler for the cpu to lower temp’s and also would perform better with lower temps, also temps are not wrong.

      • Bekim June 10, 20207:10 pm

        almost forget hurry change your cooler go with deep cool is compatible with lga 1151 and also lga 775 sockets it doing pretty damn job for me it setes temp at 45 C at idle max temp.

        • ThreadStripper June 10, 20208:43 pm

          Looks like the stocker cooler is not that good. I had a Cooler Master i117 laying around and it worked surprisingly well. It’s smaller, lighter and much quieter than the stock cooler (my ears were bleeding). Now my load temps are 20°C lower. A micronode update also fixed my BIOS issue.

    • Thedude June 24, 20206:28 pm

      I had similar “unleash”message with my asus p5q pro, I updated the microcode and it solved the problem

  • José June 2, 20208:12 pm

    Con mi placa asus p5g41t-m lx3 con shockers 775 Windows 10 32 Funciona perfectamente Pero Cómo Windows 10 64 bit No me lo deja cargar Debe ser un defecto de la plata Creo no Me lo deja cargar Y como todos los juegos Nuevos piden un sistema operativo de 64 bits Pues no me vale el invento para nada Y tengo el procesador Zeon x5470 de 150 vatios A 3,3 De velocidad O sea No te compres un procesador zeon

  • Sever June 8, 20204:08 pm

    >Let us know if this mod worked on a motherboard that isn’t in our list

    Asus P5QL SE (last BIOS form official site modded by MTOOL) works with Xeon E5440 SLANS (not overclocked).
    The hottest core idle temperature ~+60C (by hwmonitor 1.39), ~+47C (by AIDA64Extreme 5.50.3600)
    Cooler – Igloo 5063Cu PWM 1906 RPM (Q-FAN Optimal mode).

    Sorry for my English

    • Sever June 8, 20204:10 pm

      Windows 10 x64 starts with Intel SpeedStep DISABELD, C-STATE DISABLED, S3 state only

  • Kdaddy June 12, 20201:14 pm

    A request. I understand that NO netburst microcode has been added. However, is it possible that the microcode for the Xeon 5060 , Xeon 5063 , Xeon 5070 , and Xeon 5080 be added?

    The above Xeons are the 771 equivalents of the Pentium Extreme Edition 840 , 955 , and 965. They all have 4 logical cores too.

    The Motherboards with the 955x and 975x chipset would greatly benefit from this seeing that it is next to impossible to find the EE 840 , EE 955 , or EE 965 today.

    If someone could help out that would be GREAT!

    Thank You!

  • fotis skodras June 13, 20208:13 am

    1) mobo: ashrock g31m-s
    2) cpu: xeon L5430
    They are working fine (i’ve updated the bios first to version 2.10)

  • Bernard Cohen June 14, 202011:13 pm

    Just installed two Xeon X5450s on two computers, each with Intel DP43TF motherboards. Both motherboards had their BIOS upgraded with the last (AFAIK) BIOS available. The BIOS number is: NBG4310H.86A.0107.2011.0112.1625
    I ordered both processors through Alibaba. They had both been altered and notched to fit a socket 775. I think
    carefully notching the processors using a small rat tail file works better than clipping the tabs off the socket.
    Both processors cost me $45CDN ( $33.15US ) and worked as soon as installed with no problems. I’m using the larger Intel heatsink with the locking pushpins. No heat trouble that I can see. Both systems are running Debian Testing with an LXQt desktop and no issues.

  • Davi June 18, 202011:16 am

    I’m using a G31-M7 TE Ver 6.7 from Biostar, the Xeon is a E5472 3.0GHz, FSB 1600.

    I updated the microcodes and the motherboard recognized the CPU, but there’s one thing, since the max FSB of the motherboard is 1333, the machine won’t work with all of the potencial of the processor, it’ll got stuck in 1333FSB with only 2.5GHz working, I tried changing clock ratio, overclocking and giving more power to the cpu and it doesn’t worked, on this motherboard u’ll need to use the processor with autoclock enabled to not give u any problems.
    If u guys think i did anything wrong, PLS TELL ME, because i want to use all of my processor capacity.

    • ΦΩΤΗΣ ΣΚΟΔΡΑΣ June 21, 20203:52 am

      Your motherboard supports 1333 fsb

      • ΦΩΤΗΣ ΣΚΟΔΡΑΣ June 21, 20203:57 am

        I mean supports 1600 fsb (oc)

        • Davi June 21, 202010:02 am

          this i know, the thing is when i do overclock in the bios, it shows 1600FSB but when i go to the OS and open CPU-Z it got stuck in 1333 and 2.5GHz, and idk why this happen.

  • Davi June 21, 202010:37 am

    here some images.

  • Istvanstvn June 25, 202011:51 am

    Asus P5KC, ver.: 1203 BIOS, P35 chipset, Xeon 5430 CPU, (updating bios is required to unleash its full power), pedig ez a legfrissebb BIOS, nem enged tovább a BIOS! Van megoldás? Google translate: though this is the latest BIOS, don’t let the BIOS go any further! There is a solution?


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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.