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

MODs

2,046 Comments

Troubleshooting Problems

What you should try first

Make sure:

  • You're running the latest BIOS.
  • And have FULLY reset your BIOS (use the 3-pin motherboard reset jumper, and then load the default BIOS settings on the first startup). For more details, see the previous link.

Fully resetting your BIOS will fix most problems, but if it doesn't, try the following solutions:

Solutions to common problems

I'm getting a message during bootup telling me to update my bios (on some boards, it may instead complain about an unsupported CPU). After hitting F1 (or some other key), the system will then boot and seems to work fine.

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

This usually happens because your motherboard doesn't contain the exact Xeon microcode for your processor, and it's using the similar LGA 775 microcode instead.

This typically isn't a problem (except for the annoying message), and your system will normally function fine. You can usually stop this message from slowing down your bootup by disabling Halt boot on error in the bios. However, you can also add the LGA 771 microcode to your BIOS to stop this message from appearing.

If you are experiencing any other problems besides the error message, please take a look at this topic.

Windows 8.1 won't install

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

If Windows 8.1 won't install because it says your processor is missing some functionality (like CompareExchange128), the following information should help you to get it installed.

Make sure you're running the latest BIOS

These problems are usually due to do outdated CPU microcode in the BIOS, so if you haven't tried already, make sure you're running the latest bios.

If you have the latest BIOS installed, try adding the latest LGA 771 Xeon microcode to your bios

The latest LGA 771 Xeon microcodes should contain all of the functionality Windows 8.1 needs, so we recommend adding these microcodes to your BIOS. Multiple people have successfully installed Windows 8.1 after doing this.

Full details on adding the microcodes are available: here.

My system won't boot due to an unrecognized CPU error

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

  1. Fully resetting your BIOS will usually fix this problem.
  2. If this doesn't help, try the things mentioned here.

Windows crashes during startup

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

Loading the default settings in the BIOS has solved this problem for most people.

If that doesn't help, this problem is also sometimes due to the SATA hard drive mode getting reset when you reset your BIOS to its default settings. If this setting is different than what is was when you installed Windows, Windows will likely fail to load. The options are usually AHCI, IDE (sometimes listed as ATA), and RAID.

If this doesn't help, please try what's suggested here. It's also relevant to this problem.

My system seems very slow

Read this

My system is unstable (crashing, freezing, rebooting)

Read this

My CPU fan is always spinning at full speed and is very loud

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

This problem is usually caused by not fully resetting your BIOS.

If you're still having problems after trying that, you should also try the solutions mentioned here.

My system is overheating (or running hotter than expected)

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

Your temperature monitoring program may be telling you the wrong temp

Some temperature monitoring programs don't report the correct temperature for Xeon processors, so your CPU may not be running as hot as you think. The reason this happens is they're using the wrong tjmax value, which is used to calculate the current temp.

AIDA64 should read the correct temperature by default (the temps are under Computer -> Sensor). However, you can also manually set the tjmax in many monitoring programs, which should make them also report the correct values.

Fully resetting the BIOS or adding the Xeon microcode can also sometimes help with temperature reading errors

More details available: here.

You may need a better heatsink and fan

If none of that helped, you may need a better heatsink and fan. Intel usually gives smaller heatsinks for their dual core processors, so if you were previously using one of those and upgraded to a quad core Xeon this may be the problem.

Error message saying my CPU's wattage is too high, and system won't boot

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

You'll usually get this message if you try to install a 120 W processor into a motherboard that only supports 95 W or below.

However, if the TDP of your CPU is actually low enough (and you're still getting this message), adding the latest Xeon microcode to your BIOS will probably fix this message.

If this doesn't help, you can usually bypass this message by pressing F10 or some other function key (it may vary based on your motherboard).

My system will boot up (to at least the BIOS), but my Xeon is not working as expected (or is missing functionality)

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

This section should help if your:

  • Processor is missing functionality (like Speedstep, SSE 4.1, VT-X, or CompareExchange128)
  • System seems very slow and doesn't seem to be running at full speed
  • System is unstable (crashing, freezing, or rebooting)
  • And probably many other problems

Things you should try:

 

Try adding the latest LGA 771 Xeon microcode to your bios

How to add LGA 771 Xeon microcode to your BIOS

If your system is still unstable or seems very slow, try disabling the power saving features in your BIOS

The power saving features like Speedstep (aka EIST) and C-States (C1E and others) may not be working correctly with your motherboard, and it could be causing your processor to run at its minimum speed or causing instability. You should try disabling them to see if it helps.

You can test what speed your CPU is running at with CPU-Z. It should run at full speed if you run something stressful like a benchmark or AIDA64′s system stability test.

If you're still having stability problems with the Xeon, try increasing the CPU voltage or decreasing the CPU speed

If you're still having stability problems at this point, your motherboard may be at its limit speed or power wise, or your Xeon may no longer be stable at its stock frequency and voltage. This can happen over time as all processors eventually degrade with use.

I recommend increasing the CPU voltage in the BIOS. This may make your system more stable. If you aren't able to alter the voltage (or don't want to), try decreasing the CPU ratio (sometimes called the multiplier) or reducing the FSB speed. This will run the processor at a slower speed, which may make your system more stable.

If that doesn't help, you may need to adjust other voltages or speeds related to the chipset, FSB, or memory. If you're not familiar with how to do this, I recommend searching for a core 2 quad overclocking guide. Even though you're not overclocking, it should cover what to adjust to get your system stable.

If your system is still unstable at this point, try reinstalling your old LGA 775 CPU to see if it still works

If your system works with your old processor, your system probably wasn't damaged during the mod. However, we have heard of two cases where a socket pin was bent or broken, which caused the Xeon processor to not work correctly, but the old LGA 775 processor still did. So, you should definitely check for broken pins.

However, if your old processor doesn't even work correctly, make sure you've fully reset your BIOS. If it still has problems even after resetting, read this.

And if none of that helped, try reinstalling Windows

Your Windows installation could have gotten corrupted, which could be causing problems. Reinstalling Windows has helped for multiple people that were having problems like rebooting, BSODs, or other lockups.

I'm just getting a blank screen when I turn on my computer

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

Make sure your motherboard is compatible with your Xeon

If your motherboard has an incompatible chipset, your bios doesn't support an LGA 775 processor that's similar to your Xeon, or your Xeon's TDP is higher than your motherboard will allow, your system will likely fail to boot up correctly. This is explained in the motherboard compatibility section earlier in this guide.

However, you may still be able to get the system to boot up by doing a bios mod. Please see the previous link for details.

Check for the following common installation problems, and try the installation again

  • Make sure the 2 plastic tabs are fully cut off and removed from the socket. If they aren't, the Xeon may not seat correctly in the socket, which is mentioned next.
  • Make sure the processor is fully seated in the socket (try wiggling it slightly). This is a common problem that often happens if the plastic tabs in the socket are not cut off fully (but it could still happen even if they are). If the processor isn't seated correctly, it will not be able to make contact with all of the pins in the socket, and the system will likely fail to boot.
  • Adapter not lined up correctly on the bottom of the Xeon. If the placement is off by even a little or covers something it shouldn't, you'll likely run into problems. Use a magnifying glass to verify the adapter is aligned correctly.
  • Adapter is not tightly attached to the processor. If the adhesive is weakened, the adapter may move when installed in the socket, which can cause problems. Try pushing on the top and bottom of the adapter a little to make sure it doesn't move.
  • Top-right edge of the adapter is too long and covers some of the pads on the processor. If this happens, you'll need to cut the top-right edge to make it shorter.
  • A pin in the socket is bent. It's possible some of the pins got bent when you were removing the two plastic tabs from the socket. If you notice bent pins, we recommend that you try to straighten them using tweezers and a magnifying glass (a small knife may also help).

Even if none of these seem like the problem, I still recommend rereading the installation instructions carefully and trying the installation again. You may notice something or fix some issue that you missed the first time.

Try adding the LGA 771 Xeon microcode to your BIOS

Most motherboards should work fine if your bios supports one of the similar LGA 775 CPUs mentioned in the motherboard compatibility section. However, it is possible your motherboard may need the exact LGA 771 Xeon microcode in order to function properly. This microcode can be added with a bios mod. You can find more details on obtaining a bios mod for your motherboard at the previous link.

Try reinstalling your old LGA 775 cpu

If you're still having problems, you should reinstall your old LGA 775 cpu to make sure your system is still working correctly.

If your system works with your old processor, your system probably wasn't damaged during the mod. However, we have heard of two cases where a socket pin was bent or broken, which caused the Xeon processor to not work, but the old LGA 775 processor still did. So, you should definitely check for broken pins.

However, if your old processor won't even work, please read this.

If you're still having problems

If you're still having problems after trying the above fixes (including the bios mod), you can try the following as a last resort.

Try another adapter

The adapter may be defective, so I recommend contacting the seller for a replacement.

If that doesn't work, try another Xeon processor

If you're still having problems with the replacement adapter, your Xeon CPU may be defective, so I recommend returning it for another.

My old processor no longer works

Note: Make sure you try the things mentioned in What you should try first if you haven't already.

The most common cause of the old processor no longer working is bent socket pins. It's possible some of the pins got bent when you were removing the two plastic tabs from the socket. If you notice bent pins, we recommend that you try to straighten them using tweezers and a magnifying glass (a small knife may also help). We've also heard that you can use a mechanical pencil for fixing bent pins.

If bent pins aren't the issue, make sure the socket doesn't have any stray pieces of plastic (from when you removed the tabs). It's possible this could be stopping the processor from seating correctly in the socket.

If neither of these help, we recommend that you try to install your old processor again. It's possible it wasn't making a connection with all of the socket pins. Wiggling the processor when it's in the socket can sometimes help.

2,046 Responses

  • Rob May 17, 20188:57 am

    Hello, I have a question. I have a motherboard (ASUS P5KPL-VM, which has G31/ICH7 chip), then … what would happen if I install the Xeon X5470 ?. The maximum of TDP. of this motherboard is 130W., I wonder if I install that processor on this board.

    Could it get to overheat ?

    Could the board die? or

    Would it need better refrigeration?

    I’ve also been seeing that it has 3 vrm phases without a heatsink, I do not know if that can cause something in the heating up.

    Or directly move from this board and upgrade to a more current system like the 8th Generation of Intel?
    Thank you.

    Reply
  • vinod May 18, 20181:08 am

    I bought a asus p5g41t-mlx motherboard and I have done the bios update with the micro-codes, but after i power up the mobo with my xeon processor e5450 (which is modded), it stays a for about 20 secs and switch off automatically…. What should I do?, is there any changes to be done with the cmos ratio/ values? Please help
    My specs are – ASUS P5G41t-mlx
    Xeon e5450
    2GB DDR3
    palit 750 ti dual
    320HDD

    Reply
    • kjafkjkaf May 20, 20182:45 am

      change the cpu fan it turns off cause of overheat

      Reply
  • tom May 18, 20189:56 pm

    Hi

    I have a Q9550 and I would like to make a mini-itx HTPC. The best mobo that I can find is the Intel DG45FC.

    Some reputable websites say this CPU and mobo are compatible, yet, others say they are not compatible.

    Please help!!! Will the Q9550 work with the DG45FC?

    Thanks

    Reply
  • Kevin May 25, 201811:25 pm

    Hello i had some problem that my xeon is too damn slow the xeon even cant load windows in 4hours.

    But i do few tricks that i install windows on my pentium dual core and then i replaced to xeon procesor. ZThe boot works but take around 10minute to go to the desktop, and the cpu load is soo danm high, cursor stuter (even its fresh install) .if im going to reinstall windows with xeon processir it will freeze. ( in this trick if i go to safe mode, the xeon worked fine without any problem)

    Hope you can solve my problem

    I cant install windows 7 with xeon l5420, the installation takes forever so i do it with my dual core and swap the processor to xeon.

    Reply
  • john789 June 1, 20189:53 pm

    I am very interested in doing this, as I didn’t even know that it was even possible, but I need some help.

    Here goes:

    My motherboard is a Gigabyte GA-P35-DS3L version 2.0 with 4 sticks of PC2-6400 2GB 2X1GB DDR2-800 for 4Gb of ram and a E2160 cpu overclock to 3.0 ghz. I checked the motherboard compatibility list and my mb is approved.

    I read the article here https://www.delidded.com/lga-771-to-775-adapter/

    But I still have a few questions, do I need to mod the bios to Update CPU Microcode in an Award BIOS? If so, I would like the keep the microcode for the E2160.

    I would like to get either the E5450 or the E5430.

    Also can you tell me what bios settings I need to make in the bios for this to work?

    Thank you.

    Reply
  • Zach June 1, 201811:29 pm

    Confirmed this mod works on a Foxconn g41s-k motherboard with a L5420 Xeon. This Motherboard has a Max tdp rating of 65watts. Its not just plug and play though you will have to install a modded bios to bypass the CPU Max tdp warning screen. I was fortunate to have found one with the proper microcodes added as well.

    here is the link.
    https://drive.google.com/file/d/1yKntmXov7IySG1siuRbHtN1h3ua_5xfc/view

    This mod should also work on the g41s motherboard as well.

    Reply
  • dev893 June 3, 201812:20 am

    So I have the CPU installed and first boot it works fine then if I reboot for any reason it freezes on the windows 10 boot screen, I’ve got the updated BIOS with microcodes, I modded the socket and added a sticker to the CPU I had to put the C2D e8400 back in, is it possible it’s a bad CPU?

    Reply
  • Andrew June 6, 20186:58 pm

    Hello,

    I have P5B-MX mainboard which supports upto Q6600 Core 2 Quad CPU.

    I’ve got Xeon E5405 CPU (4 Cores 12MB cache, 2GHz, 1333 MHz FSB, 80W) for BIOS modification

    0. attached LGA 771 to LGA 775 adaptor to the CPU
    1. downloaded P5B-MX BIOS ROM file
    2. deleted support of Intel D and Intel 4 CPUs microcode
    3. injected suggested microcode for CPUIDs 1067a/10676/10677
    4. programmed P5B-MX mainboard with resulting BIOS
    5. attempted to boot the computer with Xeon E5405 and boot failed

    Did I make any mistake? Is there a reason why P5B-MX refuses to boot with Xenon E5405?
    NOTE: P5B-MX, FSB 533/800/1066(o.c)MHz, THD 130W

    I have put original E2200 CPU back in P5B-MX mainboard and the computer boots fine.

    Modified Xeon E5405 works fine in HP Vostro 220s computer without any issues (run Knoppix for a day).

    Thank you,
    Andrew

    Reply
  • Sushil June 20, 20185:44 am

    Hello,
    I have ASUS P5G41C-M LX motherboard which booted perfectly fine with Xeon x5450 with the help of this mod.Before adding the cpuid patches, i was able to boot up the system with windows 7 but the system didn’t boot with Windows 10 x64 bit. After using the modded bios the system is working perfectly fine so far.I have also added Dell Slic 2.1 for Windows 7,so i just hope it would be useful for someone else.

    ASUS P5G41C-M LX Modded Bios:https://drive.google.com/file/d/1pX41QZvNR7ITQzIudbzmf8QgOdi7AKue/view?usp=sharing

    Reply
  • sprit June 21, 201812:55 pm

    i have a asrock g41c-gs r2.0 will a x5460 work on my motherboard if i already have a q9400

    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.