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

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1,403 Comments

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 $20 (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

1,403 Responses

  • Eric Yu August 16, 201612:32 pm

    So I have a MS 7525 motherboard and I have a Intel Xeon X5260. After I did the mod and put the cpu in, it says that it is not supported. I updated the bios to 5.31 Rev. A and still doesn’t work. What’s the problem?

    Reply
  • ivanych_novichok August 18, 20164:51 pm

    х5450 установил на p5n-e sli, все работает, но система запускается только через рестар, проги работают нормально, но не устанавливаются игры, а те что уже установлены вылетают примерно минут через 10-15. поменяв камень на е7600 (ни чего не перепрошивая и не переустанавливания системы) все игры устанавливаются и не вылетают! в чем причина я не знаю.

    Reply
    • Barto August 19, 20163:41 pm

      tray us my config CPU 1334mhz and ddr2 667mhz and vcor 1,25 v and ddr 1,92v. All ddr setup is defult. CPU and DDR is unlinked.

      Reply
  • Barto August 19, 20163:36 pm

    P5N-e SLI L5420 worked and tested

    Reply
    • ivanych_novichok August 19, 20163:50 pm

      а где скачать биос под L5420? спасибо.

      Reply
  • Tilek August 20, 20168:00 pm

    i have intel broadwater q963. which of processors xeon will work on my chipset?

    Reply
  • Francis D. August 21, 20169:22 pm

    Hello.
    HP elite 8000 can only boot a Xeon processor with a corrupted Cmos. You need to corrupt the cmos, by pressing the cmos button on the motherboard.
    So no reboot is possible. Also, you can’t save bios settings, you need to press F2 or other function keys, to boot into already installed OS, like Windows 10, or Ubuntu. You also can’t install a new OS, like Windows or Ubuntu, you will get errors if you try. Tested with Bios 1.14, Xeon X3353 cpu, it is possible to boot into Windows 10, also Ubuntu live cd, but system may hang as soon as a new device is detected. Recommended only for experimental purpose, totally unstable and not really usable.

    Reply
  • Miklos Potyok August 22, 20168:29 am

    Xeon L5430 works on Asus P5K-VM motherboard with recent (AMI) BIOS ver. 1001 patched with Xeon microcode (cpu0001067a_plat00000011_ver00000a0b_date20100928.bin and cpu0001067a_plat00000044_ver00000a0b_date20100928.bin) by MMTOOL_3.22_1B_21Fix-BKMOD.EXE utility. I run L5430 at 2.84 GHz (355MHz FSB) and 1068MHz RAM speed (2x1GB KingMax DDR2-1066).

    Reply
  • anon August 24, 20166:21 am

    Intel Xeon X5470 is confirmed working on G41MT-S2PT.

    :)

    Reply
  • Root August 24, 201611:59 am

    Hi!

    *I have a Xeon X5450 CPU and Ga73pvm-s2 motherboard.

    *Xeon X5450 running at Ga73pvm-S2H model, i check out.

    * Do Xeon X5450 runs at Ga73pvm-S2 model?

    Reply
  • cheatyx August 26, 201611:01 am

    Hi, i upgraded my p5q Pro from a Core 2 Duo to Xeon e5462 Quad Core, it works, but windows only show me 2 cores! Anyone has a solution?

    Reply
    • cheatyx August 26, 201611:26 am

      Found it, unselect the box in msconfig->boot->advanced

      Reply

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.