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

MODs

2,148 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 $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

2,148 Responses

  • AITIRE September 17, 201810:15 am

    Tested GA-EP45-UD3LR with Xeon x5460. Works fine.

    Reply
  • Null September 24, 20182:25 am

    MSI G41M-P33 (MS-7592 / VER: 3.0) [Not the Combo model] with Xeon E5450 (SLBBM / E0) made it pass post but failed to boot Windows 10 at first. Then I flashed my modded bios and now it works great; no issues here. Should have flashed it first, thank goodness for M-Flash.

    Thank to everyone involved with this guide.

    Reply
  • Yaboi September 26, 20183:23 pm

    Am i the only one that go lost at the part where it listed the geforce 9400 GPU as a compatible chipset?

    Reply
  • doomydan September 29, 201810:15 pm

    Gigabyte EP35-DS4
    E5450 (SLANQ)

    Flawless! Running stable at 3.78GHz.
    Almost perfectly matched with a Geforce GTX1050, where they kind of bottleneck each other depending on the game.

    Reply
    • Albert October 4, 20188:51 am

      Did you flash the bios?

      Reply
  • Eu Gene September 30, 20189:24 am

    MSI P45T-C51 working well with X5460 revision E0 (SLBBA)

    Running at stock 3.16GHz

    Used BIOS update found at: http://genius239239.myweb.hinet.net/771/?MywebPageId=2014121394614106094

    Reply
    • Albert October 4, 20188:53 am

      When i start the bios with the first boot device on the usb downloaded on that page, appear that message: Disk Failure,no system found… Or something similar, what can i do? Motherboard: Foxconn G31MXP
      Cpu: Xeon e5450

      Reply
      • doomydan October 13, 201810:16 pm

        Yes.
        BIOS modded with updated microcodes in accordance to this guide.

        Reply
  • Michael October 6, 20186:46 am

    ASUS P5Q Turbo worked with X5470 and modified BIOS from genius239239.

    Reply
  • FatNinja October 6, 201810:31 am

    did not work on intel dg33bu with xeon e5450 co stepping, although the q9550 does work on this board. did work on asus p5ql-vm epu, after micro cord revision.

    Reply
  • Neil October 6, 201811:10 am

    Hi there anyone know where I can get two 4gb sticks of ddr2 ram.

    Reply
    • Michael October 6, 201812:00 pm

      Try to search on aliexpress and ebay with keyword “ddr2 intel”

      Reply
  • Pushti October 10, 20184:28 am

    Hello,

    I have mounted a Xeon X5470 3.33 GHZ / 1333 FSB / 120 W TDP on my very old Asus P5B SE (around 10 years) and it worked for me after modifying and installing the custom BIOS file as described on this website – thank you for this and for the accurate description and instructions.
    I have paired the X5470 with a “Thermalright AXP-100H Muscle” CPU cooler and the processor stays at around 47-50 degrees C on a hot day in idle and at around 65-68 degrees C on full load (tested with Orthos Prime and measured the temperature with Speccy and CoreTemp). I also only have two exhaust fans for the case, so I think the temperatures are quite alright in this situation.

    The Xeon that I bought was already adapted for the LGA 775 socket and after using it for about 7-8 months, this is what I can tell you about it:

    – the custom BIOS file MUST be installed as described on this website (thank you again) to make it register correctly when starting the PC

    – I have lowered the base clock from 333 MHz to about 323-324; when I used the full 333 the system was unstable

    – my DDR2 memory runs at around 400-405 MHz and is set in the motherboard BIOS as “DDR2-667”- in my case, going lower or higher (see base clock above) made the system unstable

    – in my case, the Xeon DOES work, but IT DOES NOT work perfectly – I still get a blue screen every now and then, but this does not bother me, since I only bought the Xeon to play with it with and with the P5B SE adaption. My Windows 10 installation is also quite old.

    – To sum up: I did not spend that much on the Xeon and, as mentioned before, I bought it to try to make it run on the P5B SE. As I have said, I have been using it for about 7-8 months now and I can say I am quite satisfied with the results so far. As a piece of advice: keep your old LGA 775 CPU and BIOS file as backup in case things go wrong.

    Again, I wish to thank the creators of this website for the clear and accurate pieces of information and instructions provided.

    Best wishes!
    Pushti

    Reply
    • Pushti October 10, 20184:36 am

      just to be clear:
      the memory runs at 400-405 MHz in CPU-Z which would make it around 800-810 MHz DDR2 (double data rate)
      This seems to be a “sweet spot” since going lower or higher caused system instability.

      Reply
  • sinan October 11, 201811:06 am

    İntel Skyburg Dp45SG motherboard modular xeon 5460 processor did not work did not find the bios Thank you

    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.