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 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 $15 (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

1,687 Responses

  • jvela001 May 9, 201710:11 pm

    Asrock N73V-S w/chipset GeForce 7050 modded and running a Intel Xeon X5460 (3.16 GHz Stock) at 2.85GHz , default speed supported but unstable , I prefer 4 cores at 2.85 than my old Celeron D at pseudo 1.8 GHz…..for me mod successfull…

  • SparX May 11, 20175:31 am

    Gigabyte GA-EP45-DS3P , Bios F9c with microcode update , X5460 E0 (SLBBA). EIST and C1E are on and system is stable with stock copper core 775 cooler. AIDA stress test sees cpu temps reach ~71’c. Cinebench cpu score 351… [Imgur](http://i.imgur.com/zz1SGv1.jpg)

  • HankDeluxeEd May 12, 201712:15 pm

    Asus P5K PRO, rev 1.xx, Chipset P35 rev. a2, FSB 1333, CPU X5470 Stepping 0xAh;

    Updated Bios ROM ver. 1303 with mmtool. Now have VT-x

  • tster333 May 13, 20173:03 am

    So I got Gigabyte EP41T-UD3L and E5335 I did the mod works like a charm

    I also got P41T-D3P and E5335 and E5430 works as well.

  • Vu Dang May 16, 20177:10 am

    I ordered another cheap 771 Xeon: X3323 at $8 on aliexpress. Work well on my Asus P5WDG2 WS PRO (i975X). Only minor problem: Bios show only 2 cores but in Win 10: 4 Cores with VT-x and all instructions MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, EM64T, VT-x. And CPUZ detected as E5420 in the name line (specification line: X3323)

  • dibox May 19, 20172:50 pm

    Mainboard Intel DP43TF BIOS ver 0107 (NBG4310H.86A.0107.2011.0112.1625)

    I have tested three processors.
    The first was
    Xeon E5450 Stepping E0 (SLBBM)
    1)The motherboard recognizes the processor.
    2)Fans spins at full speed no matter which system is curently running.
    3)System won’t boot on a restart or reset, but it does boot if you shutdown first.
    4)Windows 10 Pro 64 bit stops loading at first screen. Also can’t install from DVD/USB.
    5)Windows 7 Ultimate 64 bit installed without any issues but lacks support for some instructions like (Intel SpeedStep Technology, SSE4.1 and VT-X).
    6)Puppy Linux (Slacko64 Puppy 6.3.2 and Tahrpup64 6.0.5) works fine.

    The second and third were
    Xeon E5440 Stepping C0 (SLANS) and
    Xeon E5450 Stepping C0 (SLANQ).
    Both functioning without any issues and with all instructions on Windows 10 Pro 64 bit.
    Have Fun with moding :)

  • adam123adam May 19, 20176:35 pm

    E5450 SLBBM (E0) works on Ga-G33M-S2 with latest original (NO MODDED) BIOS (F7k)


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.