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

MODs

2,431 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 $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

2,431 Responses

  • Ver January 25, 20202:11 pm

    Материнская плата ASUS P5GC-MX / 1333
    Скажите пожалуйста какой xeon можно поставить? И вообще , можно ли поставит.? После прошивки.

    Reply
  • JonBenz January 27, 202010:28 pm

    ASUS P5Q Deluxe + x5406 E0 working!
    Intel Eaglelake P45
    ICH10R

    I made this MOD work on a ASUS P5Q – Deluxe with a X5460 E0 stepping

    With the latest BIOS from ASUS v2301 the system recognize the CPU but it gives a warning telling that you should update your BIOS to unleash all the features in the processor (you can skip that warning but the system won’t boot).

    After i installed the Modified BIOS, the warning message is gone and system boot perfectly.

    I am getting 43 degrees on stock. I will begin to overclock this cpu.

    Reply
  • Pat January 31, 20206:59 am

    Mod done on ASUS P5QL-E running a X5460
    System is stable, however some programs report problems with the SSE 4.1 and missing instructions (So far only UbiSoft games) even with instructions added, currently investigating.

    Other than that no issues

    Reply
  • Robert February 6, 20202:35 am

    Dell Optiplex 380 and 780 works with the X3350 CPU

    https://drive.google.com/open?id=1-DYd0kiXjW-1fJidiMFyMkXsJ_tbGJTS

    Reply
  • Ste February 13, 20206:56 am

    Hi there I got myself a ASUS P5K64 WS mobo running pretty, I bought a xeon X5470 to breath some new life into it. According to the mobo compatibility charts my mobo shud be compatible with a xeon x5470, I been trying everything in my power to make it work, bios flashing and all the rest but to no vail. I followed all the troubleshooting guides i cud find and been reasearching on the net in case I was missing something, no matter what I did I’m still stucked. Any help or tip will be greatly appreciated, cheers!

    Reply
  • Игорь February 15, 202011:44 pm

    G41MT-S2PT проц Intel Xeon E5430 невозможно установить Windows 8.1 так как процессор не поддерживает CompareExchange 128 какую прошивку биос поставить ?

    Reply
  • najime78 February 16, 20201:49 am

    Good morning all.

    I got a GA-X48T-DQ6 (rev. 1.1) motherboard with chipset x48

    https://www.gigabyte.com/uk/Motherboard/GA-X48T-DQ6-rev-11/sp#sp

    I dont know what cpu to use,and having problems figgering out between x5 en x3 series cpu.

    Im looking for a xeon that is compatible with my motherboard (for example a 1600 bus speed or 1300 quadcore)

    Could someone tell what cpu i can use?

    would help me out big time..!!

    Thank you.

    Regards,

    najime

    Reply
  • ingus February 16, 20205:46 am

    do i need custom bios for nforce 680 sli? if so can you send me custom bios??

    Reply
  • Jim March 2, 20206:13 am

    QUESTION for ANYONE who has any idea about the dual core Xeon 50xx series CPUs (like the 5060). They seem different from all the other models as they have hyperthreading. The 5060 has 3.2GHz clock speed with only 667MHz FSB, so I’m wondering weather it would be good for overclocking on motherboards with the dreaded FSB wall, as is the case with G31/G41 motherboards. Most of these Xeons have a 120w TDP, but a couple are 90w and they would probably be the ones I’d go for. I’m not sure if they would even work, or if they do, would having HT on these chips would require different microcodes a bios mod? I guess if nobody has tried it I could just buy one and give it a go, the CPUs are cheap enough. Any thoughts…?

    Reply
  • Alex March 6, 20204:06 am

    asus p5kpl + e5405, I need bios, help if you can

    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.