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 $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

2,254 Responses

  • Andrey June 24, 20183:37 pm

    Hello, you can do the BIOS for asus p5e ws professional?
    here is the link to the original BIOS:

  • NickOS June 25, 20186:30 am


    I have a HP Compaq dx2400 Microtower PC with motherboard IPIBL-LB (Benicia) According to the below https://support.hp.com/us-en/document/c01324212

    it works with Intel Core 2 Quad (Y) Q9xxxx

    I would like to ask if anyone have tested the aforementioned mobo with Xeon E5450 (close to core 2 duo Q9650) with adapter.




    • Silvestar Šantak July 5, 20181:12 pm

      Tested the mentioned dx2400 with Xeon X5470 and new Noctua cooler.
      works perfect!

      • NickOS July 6, 20182:15 pm

        Thanks for your reply! Did you need to update the bios with microcode for xeon? If yes let me know the steps to follow, please

    • Beppe July 6, 20184:52 pm

      Hello everyone, i want to help who have the IPIBL-LB motherboard, to provide microcodes and ORIGINAL and PRE-MODDED bios for XEON 65nm and 45nm

      Download Link Here: I think you can appreciate, thanks!

  • Gnarf June 29, 20184:59 pm

    I have a Asus Rampage, will performing test and updating this thread with the results. Got a 5460 and a E5450 to test with =)

    • Gnarf July 19, 20188:28 am

      Hi again.

      X5460 SLANP works perfectly with my Asus P5Q Pro. I Had the latest official 2201 BIOS but mb kept nagging about “update BIOS” and I could reach an stable overclock of 3.96Ghz. However I inserted the microcodes to get rid of the message at bootup – SUCCESS!
      My RAM probably stops me from getting more OC, POST and W10 is OK at 4.25Ghz but Windows freezes after a few minutes.

  • Greensmack June 30, 20187:43 am

    I wanted to report that I was successfully able to use a Xeon X5492 processor on the motherboard “Asus P5Q Deluxe”.

    The list didn’t show this as being previously tested/compatible. The MB itself provides the same FSB (1600), but the CPU was not indicated as known to be compatible.

    I am running the memory at 900mhz;I set the bus speed to 450mhz and the cpu multiplier appears to be capped at 8.5x. This hasn’t proven to be a limitation in my tests; speedstep also drops the speeds down when the computer is idle. I am using all of the regular power saving features and am on stock voltages.

    The basic testing and OC provided a total of 3.8ghz. I was worried about the RAM speed jumping like that, but it is working great. I intend to do more tweaking; it’s worked fine for over a week with a couple 24×7 days during that time frame.

    I had previously modded the board 3 or 4 years ago and had been using an x5460. That allowed for this upgrade to go fairly smoothly.

  • Raketin July 1, 201811:05 am

    I need the modded bion for the Msi P35 Platinum i have a x5460

  • Raketin July 2, 20187:06 pm

    P35 Neo2-FI / P35 Neo2-FIR / P35 Neo2-FR
    P35 Platinum / G33 Platinum (MS-7345)
    this models have the same bios does this mean that i can use one modded bios from a p35 neo1-Fl and it would work?

  • mochikac July 11, 20186:53 am

    successfully did the mod with xeon e5420 on g31-m7 te

  • Kleber July 13, 20189:09 pm

    ECS G41T-M7 Mod Xeon,alguem por favor.

  • Georgi July 15, 20189:58 am

    Jetway i35p-sg with Xeon e5440 (E0).
    It started without any problems at 333FSB x 8,5.
    Curiously core #0 is about 10 degrees hotter than the others

  • Big Smoke July 15, 20182:53 pm

    I want to submit a failed attempt on an Asus P5W DH Deluxe Revision 1.02g Bios 3002
    Tried to run a Xeon E5450 E0 SLBBM but had no luck to get it stable.

    On Stock speed the PC barely booted into Windows, but crashed immediately when opening an application with some heavy cpu load.

    Tried different FSB Speeds and found some kind of sweet spot around 300 MHz. In combination with increased FSB Termination Voltage, booting into Windows was not a Problem. I could even run some benchmarks and test some games. But in the end it was not stable enough, after some 5-15 mins the PC crashed with a BSOD or just rebooted.

    Tried different BIOSes, premodded and selfmodded ones – noch change.
    Tried different RAM configurations, single stick, dual channel, 667 MHz or 800Mhz ones – but nope.

    Lowering the FSB even more in the area of 200-266 lead to even more unstable behaviour – weird.
    Increasing voltages in the Bios for ICH and MCH didn’t help either.

    Disabled EIST and C1E, worked through the troubleshooting section, but that wasn’t the solution either.

    Btw. the PC runs fine with an Core2Duo E5500 overclocked @3.4 Ghz


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.