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

2,386 Responses

  • Juergen June 3, 20199:36 am

    works this modifikation with the Motherboard Foxconn 946GZ7MA-8KS2H?
    I can not find a update for the bios.

    Thanks in advance

  • Nathan Swann June 14, 20194:50 pm

    Need a bios update for the xeon to work on my asus p5k premium motherboard?

    • Cikmeliksitir October 19, 20195:04 am

      I bought E5440 from aliexpress and replaced it with pentium e5200 and it stuck on post.
      Normally it must detect rams and sata.
      My mobo is G31M-ES2L.
      I can’t find any help for it!

  • Delgrand July 3, 20194:43 am

    E5450 (E0) tested in P5E-VM HDMI, working perfectly (microcodes applied previously)

  • AnJy July 13, 201910:25 am

    Was able to get a xeon e5450 working with as asus P5QL-VM DO motherboard

  • Andreas July 16, 20191:04 pm

    E5472 works on Asus P5k EPU after Microcode update. Fsb 1600 MHz, 4 x 3GHz, RAM 4×2 GB on 1066 MHz. No other OCing applied

    • Andreas July 16, 20191:17 pm

      I forgot to mention, I had to uninstall all cores separately in device manager after the upgrade (reboot only after uninstalling the last) because it was still showing the previous cpu in Windows, even though it showed the right one on boot screen and in bios. After reboot the right cpu installed automatically. One final sidenote: while inserting the new Microcode with the recommended Programme, there was a Message like: storage capacity is full or something. So first I had to delete one other Microcode, after which I succeeded in inserting the new Microcode. The one I chose for deleting was the one with the oldest date, probably the one for celerons. So these oldest processors won’t work now on my machine, no problem for me.

  • Flint July 18, 201912:00 am


    Xeon x5472 worked 16GB DDR3 running 1600MHz Fast
    Supper fast

  • Vath July 30, 20198:07 pm

    Gigabyte GA-965P-DS4, Rev 2.0, bios F12 works with Xeon E5420 (Harpertown E0, FSB 333, 45 nm, 1067A). Used method 2 for microcode update.

  • eddy August 11, 20196:05 pm

    Gigabyte GA-P35-DS3P

    Xeon X5470 Worked after Bios-update to F12!

    • AnJy August 16, 201912:12 pm

      I’ve got this wierd problem with this mod. I was able to get a xeon e5450 working on an asus p5ql-vm do motherboard. And after several days the the computer turns on but gives no signal or mouse and keyboard input. The only way the fix this issue is taking the processor out and cleaning the lga pads with 90% alcohol. I have a set of pentiums which both work instantly without cleaning and if i just reseat the xeon it still wont post. The problem is that its just annoying to have to take it out every week or so when it stops booting.

  • LUPINtheTHIRD August 15, 20194:45 am

    Asus P5KPL-CM, Xeon L5410 SLAP4 working after adding microcode and updating bios to latest on asus website. Unable to overclock it neither of 1Mhz (dont know why prime95 reporting error when modifing BUS FREQUENCY)

  • Kevin August 16, 20192:36 am

    Hello there! Please, I have 2 motherboards:

    – ASRock G31M-GS
    – ASRock G41M-VS3

    I would want to put a Xeon x5450 in each. Is it possible? What about the TDP?

    e5450 have lower TDP but is a little bit expensive than x5450 (and x5450 there isn’t in my country, need to buy from ali or ebay).


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.