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

MODs

2,148 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 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 $14 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

2,148 Responses

  • tailland October 14, 201810:19 pm

    I’m about to order a pre-modded E5450 for my GA-EP45-DS3L.
    Do I also need to create a modified BIOS for this?

    Reply
    • Michal October 15, 201812:57 pm

      Got this cpu and motherboard and no modifications in BIOS are needed.

      Reply
      • tailland October 15, 20184:34 pm

        Not just to run it, but also to unlock all of the CPU’s features ? That would be great.
        I was already happy enough to have found genius239’s website, for he has a pre-modded BIOS for the board.

        Reply
  • Adrián October 15, 20186:46 pm

    Hi, I have an X5460 in a G31M7-it works fine. I bought a p5p41t-le but I can not find the corresponding microcodecs. I downloaded these pages but none worked.
    http://genius239239.myweb.hinet.net/771/
    http://tanieprocesory.pl/en/bios2-2/
    I need to mount the Xeon in the mother ASUS since it is a newer technology.
    I would appreciate any help. Regards.-

    Reply
  • Chris October 19, 20185:50 am

    E5450 works fine on Fujitsu D2841-A1 after microcode update with Update-tool from Fujitsu Website. (got some microcode error before with only updated BIOS)

    Reply
  • Brad October 19, 20188:58 pm

    Was able to get Xeon L5240 working on Abit IP35 Pro with bios revision 17 in Win 8.1 Pro. Had to reset the CMOS jumper to have it recognize it. CPU id showed E3110 in the header and L5240 in the detail section.

    Reply
  • sulko October 20, 20185:44 am

    DFI LANPARTY BI P43-T34. Xeon E5450 works fine.

    Reply
  • RayF October 20, 20182:21 pm

    Is the GA-Q35M-S2 motherboard compatible with x3363?

    Reply
  • Joey October 25, 201811:43 am

    Intel Xeon X5460 successfully tested on Gigabyte GA-EP31-DS3L rev 2.0, with modded bios, downloaded and flashed from: http://genius239239.myweb.hinet.net/771/

    Reply
  • Mugur Stefan November 1, 20181:57 pm

    L5420 works with DELL 380, EP45T UD3R and EP45 UD3RL ,

    X3353 works with EP45T UD3R and Intel DQ45CB

    Reply
  • PaulieLUL November 5, 20187:38 am

    Old cpu: C2Q Q6600
    New CPU: Xeon X5460 (SLBBA)
    Mobo: Gigabyte GA-P35-DS3L (newest bios version from official website – F9)
    RAM: 4X1 GB DDR2 800 MHz Transcend
    PSU: 620W Seasonic
    GPU: Asus HD7970 DirectCU II

    With the new Xeon the PC goes to bios without a problem, it shows xeon running at 3.16 GHz (which is the stock speed. But when I start booting from my SSD it is stuck on windows logo forever. Can’t even reinstall the windows (stuck with same problem)
    I tried resetting to default in bios settings and it didn’t help. I will try reset the bios hardware-wise with jumper or by removing CMOS battery. If it won’t help I will try custom bios on the genius website.

    Reply
    • PaulieLUL November 6, 20181:06 am

      Update 1: BIOS fully reseted to by shorting 2 pins on the motherboard (no jumper). It didn’t help so I followed the guide how to inject microcodes to the latest bios. When I tried to use Q-flash to update the bios it didn’t recognize the usb thumbstick, only floppy drive A and floppy drive B (which are not even in my computer) I tried two other thumbsticks of course formated to FAT32 before I copied the bios on to it and it still didn’t detect my USB flash drive. Guess I will have to either put old cpu back and somehow it will be fixed or updated the bios via command prompt in windows.

      Reply
      • PaulieLUL November 6, 20182:13 am

        If anyone is interested I can send over latest bios (F9) for GA-P35-DS3L injected with Xeon 1067a (X5460) CPUID microcodes.

        Reply
        • PaulieLUL November 12, 20184:58 am

          Update 2: I was finally able to flash my bios with the bios + xeon microcodes, I had to do it with the old hardrive in bios with utility called @bios. Everything works now, running X5460 at 4 GHz, 1.325 V

          Reply
  • Igor Havran November 5, 201812:28 pm

    ASUS P5Q + Xeon X5482 = Worked fine on 3.2GHz and FSB 1600

    Reply

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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.