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

2,483 Responses

  • Marco April 18, 20202:44 pm

    Tested on asus P5B plus Vista Edition (P965), BIOS 1103 with microcode and Xeon E5450 (SLANQ, cpuid 10676) from alix.. already modded: running perfectly!!

  • ghost April 19, 20204:51 am

    gigabyte g41m-combo rev 2.0 – xeon e5450 c0 works perfectly

  • BIGPRI470 April 22, 20205:57 am

    hi I would like to modd the motherboard asus P5GD1 with Xeon x5460, does anyone know if it works, I would like to avoid throwing money for this thing.

  • Sílvio April 22, 20207:24 pm

    Hi there!
    Thank you for the information on the Xenon processors!
    I’ve read in same websites that this processors, as they were designed for servers, would need ECC RAM Memory.
    If so, can u tell me if a dual channel 8 Gb (4×2) DDR3 1333Mhz wouldn’t perform at it’s best?

  • Ali Muhana May 1, 202010:36 am

    Xeon x5420 works on Biostar GF7050v-M7

    • Kyle May 14, 202010:23 am

      Hi, I’m using an old ASUS P5E Motherboard. The chipset is x38. I have purchased a modded 771 to 775 Xeon X3363 cpu. I’ve installed it and it works but with a few issues.
      It’s not registering the temperature correctly and the fan is maxed out. I’ve reset the bios, it didn’t fix this so I’m assuming I have to add the microcode to the bios? Will that sort out the missing cpu instructions? Thanks.

  • Piecutter May 4, 202010:08 pm

    Just for fun, Dell Optiplex 360, A07 bios, went from E5300 2.6g to a X5460 3.16g with no problem.

    • Donathan May 12, 20209:02 am

      Im planning to upgrade from an e5300 optiplex with ddr3 ram to a either a x5460 or x5472, which would you recommend and can you overclock with the stock motherboard?

      • Piecutter May 12, 20206:42 pm

        The only reason to use an X5472 would be if it were free. The 5460 has a higher base frequency. It just does everything faster. The only difference on the 5472 is the memory frequency, which doesn’t make a difference on this system. Get the X5460 SLANP if you can find it. As far as OCing goes, it’s a Dell, so don’t get to excited unless your willing to go down the custom bios rabbit hole. This is 120w TDP, so upgrade the PSU before you try to do anything serious, or if you’re planning to put in a high watt gpu. And 4gigs of DDR2 is all you can do. The socket won’t take ddr3.

        • Donathan May 12, 202010:07 pm

          Thanks for the response, I’m now deciding between the 5450 and 5460 which do you think is the better pick. Also probably going to slap a 750ti in there or would you have any other cheap gpus in mind that won’t be bottlenecks. Also you think so you think psu will need an upgrade? Overclocking is probably not going to happen don’t want to brick the bios. Thanks again for the help anything else I needed to worry about?

          • Piecutter May 13, 20202:14 pm

            5460, hands down. Beats the 5450 in every way.
            GTX750ti is exactly what I put in this one. Definitely upgrade the psu. At least a 430 watt unit, unless you find a 500 for cheap. Get the measurements of the card first. I had to do quite a bit of modifications to get a Gigabyte GTX750ti Windforce model to fit. The PCI express 16 slot puts a dual slot card out of bounds for the 2nd slot. Only a single slot card that is not full length will fit without modifications.

        • Donathan May 13, 20202:19 pm

          Decided to get a dell t3600 with a Xeon e5-1620 should be better

  • Brad May 9, 20205:12 am

    I have done this on two diff machines now, with Xeon X5470 one on an ASUS P5Q-E and the other on a Gigabyte EP43-UD3L. Both machine easily OC’ed to 4.2 GHz at 420 x 10 even while using 400 speed DDR2.

  • Jason Mosquera May 10, 20201:07 am

    Tengo una PEGATRON IPMEL-AE funciona con asta 133hgz
    Hice el mod todo bien y sin daño alguno
    Pero ahora que pongo el procesador con su pasta térmica y su ventilador suena un pitido 6 no inicia la computadora
    Nose si es por temas de compatibilidad pero intenté de todo tenía un Dual Core E5300 A 2,6GHZ y ese me sigue sirviendo normal incluso actualice la BIOS y sigue igual.

  • Tony May 14, 20205:30 am

    I bought Xeon X5460 (E0 – SLBBA) for motherboard Foxconn 2A8CH (Intel G41 chipset). Original CPU is Core2 Duo E7500. BIOS is updated with Xeon microcodes.

    When I put Xeon in socket and turn on rocker switch on PSU, fans immediately start spinning at max RPM, without pressing start button on front panel. Nothing shows on screen. Only way to shut it down is turn off PSU. Same behavior is when CPU socket is empty.

    My questions is, CPU is faulty or it have bad connection or motherboard just not support this CPU or something else? Does anyone have experience with this problem?


  • Bruno May 19, 20209:04 pm

    I tested it on the dell optiplex 780, however, there was no video. tried all the ways, updated the bios and installed macrocodes, even so it didn’t work, I wanted some tips

    • Bruno May 19, 20209:06 pm

      processor model and the x5450, with 8gb of ram and an nvidia nvs 315 1GB DDR3 video card


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.