Hi there, I recently got my hands on this old system which I want to upgrade and give to a family member. It originally came with an i5 660 and I want to put an old i7 870 I had lying around in it. The i7 is known good, I tested it on another board.
Now, when I put the i7 on the board and try to boot Windows 10, the system will completely lock up 9/10 times during the spinny dots screen. The CPU fan ramps up to 100% and not even the reset button or holding the power button will shut down the system. In the 1/10 chance it manages to boot into Windows, the system runs absolutely stable. When I put the i5 back on the board it boots fine every time.
I ran memtest with the i7 installed and it didn’t find any problems. I also tried reinstalling Windows but it just hangs again after the installer reboots to the SSD the first time. BIOS is updated to the latest version. Linux seems to boot fine.
This is actually a good point. If you can swap the PSU try that. I’ve gotten some oddities out of PSUs going bad. You’ve mostly checked off memory and bad pad contact with the memory test, so that’s really the only thing that sticks out. You could also try toggling off features in BIOS disable virtualization and whatnot and see if it gets you booted.
If you have a copy of PC-Check it might be able to diagnose if a particular piece of the processor that isn’t working, but I’d try the PSU swap first.
Just keep the i5 and move on? It has already passed its best before date and any difference in performance will make little to no practical difference anyway?
Alright, by now I’ve tried swapping PSU, RAM, boot drive and GPU, I also tried an i5 750 on the board which boots fine every time as well.
I’ve tested the i7 on a different board again, and it works fine there. Boots fine and runs stable, also tested 2 hours with Prime 95 blend without errors.
As I’ve said this problem only occurs with Windows 10. Linux boots fine. When Windows 10 does manage to boot it runs fine, also Prime stable so VRM shouldn’t be the problem. It’s just something that happens while booting Windows 10.
For starters, Windows 10 dropped virtualization/VT-d support on Nehalem among other things, so check that VT-d is disabled in your BIOS. Even if you’re not using it.
VT-d is disabled, I also tried disabling virtualization alltogether but that didn’t help. Any other BIOS settings I should try?
I tested some more and found that the system manages to boot back up normally when I select shutdown but not when I select reboot in Windows. Fast Startup is enabled.
The i5 has additional features over that i7: AESNI, CLMUL, VMX unrestricted mode, and 1G hugepages - so if Windows is expecting those to exist then that may be a problem. Linux is less fussy. None of the CPU compatibility lists for Windows 10 mention i7-870 support (Windows Processor Requirements Windows 10 21H2 Supported Intel Processors | Microsoft Learn) but then, in typical Microsoft fashion, they don’t state exactly which instruction set extensions are required.
I disabled fast startup and as expected the system now acts just like on a reboot when I use shutdown, which means on the next boot it locks up, I have to cut power and then it boots again.
Interestingly enough I noticed that the system will also not boot if I don’t cut power long enough. I have to wait until the LED on the board also goes out and all residual power is gone to make it boot once more.
Right you are, my apologies. I was looking at the i5-750, which OP had mentioned right above your comment that I replied to. The i5-660 did indeed come out slightly later with a die shrink and a few new features.
@razorlikes, have you tried what @GigaBusterEXE suggested? Also, you could try removing the motherboard’s battery, which should put the BIOS into its default factory configuration. Finally, eliminate any nonfactory setting in the BIOS, including any saved Windows setting in the BIOS. After your BIOS is fixed, reinstall Windows to a never-before-written hard disk or SSD. I once had to do the same steps I suggested for an old comp. While I didn’t have the same problem as @razorlikes, it was similar.
I tried now and disabling HT actually seems to work. But now this kind of defeats the purpose of using an i7. The i5 660 works with HT enabled though.
I reset the BIOS multiple times. Also completely reflashed the BIOS chip with an SPI programmer since I’ve had weird problems with other boards once which weren’t fixed with a normal BIOS flash.
I don’t have a brand new drive at hand but I’ve zeroed out the drive and then reinstalled Windows but that didn’t help.
How long did you leave the motherboard battery not connected to the motherboard? Some motherboards require you to remove the battery and not replace the battery until the following day. Have you purchased a new motherboard battery? You can have weird problems with old motherboard batteries. How many times have you zeroed out the drive you used? It can take up to 7 passes to properly zero out a hard drive. You might want to check and see if the USB drive used to install Windows isn’t corrupted. Other than checking what I have newly posted, I am out of ideas.
That’s not the point, which is to diagnose the issue preventing you from fully utilizing the CPU you want would like to.
You also seem dismissive that power delivery isn’t an issue, but I wouldn’t rule it out so hastily.
What is the power draw of each of these chips? Same TDP? Temps?
How many phases and what current rating on the VRMs? How is case airflow? Temps?
What is the PSU and what is it’s power limit?
Don’t assume that because it fits that everything is universally compatible, different CPUs have different power needs even within the same generation and even with the same TDP. What matters is real world power consumption data. From what I’m reading above you’re actually dealing with two different generation CPUs so it is very possible that the older i7 is using more power and can’t hit the full boosts that the i5 can on less power.
Or like others said it could be lacking in a specific feature, but at the end of the day it is sometimes much easier to rule out the obvious stuff than it is to fish around in the dark hoping to stumble upon the answer.
10-15 Minutes usually, I also left it out for about 12 hours last night but that didn’t help.
I did try a new one, the old one had 2,95 volts under load so it was still fine.
I did two passes.
The i7 870 and i5 750 both are rated for 95 Watts TDP. The i5 works fine. 70-75C on load for both chips. The i5 660 is rated for 73 Watts.
I think it’s 6 phases? Maybe 5+1? The i7 is on the CPU support list though so VRM shouldn’t be an issue, in fact when I get the system to boot with HT enabled it runs rock solid, primestable for 2+ hours. That should give the VRMs a good test. Currently not in a case. VRMs don’t have a temperature readout but I’m using a top blow cooler so airflow should be adequate.
A 550W Super Flower “SF-550P14HE” with 4 12V rails 16A/16A/16A/18A. I’ve been using this PSU for testing hardware for years now.
The CPU, RAM, PSU, SSD and GPU have all been tested with a different board together. Everything runs there, with HT enabled. I also tested different RAM, PSU, SSD and GPU with the the P7Q57-M DO and got the same behaviour so it’s safe to say that all other hardware is known good.
Only with the P7Q57-M DO the system will not boot under certain conditions: It will boot fine with Windows 10 “Fast-Startup” enabled and when it was only shut down, but not when I select restart in Windows. Something that happens when Windows cold boots, e.g. selecting restart in start menu or disabling “Fast-Startup”, causes this issue. To make it boot once more I have to cut power for about 15 seconds.
This does not happen when HT is disabled or any other OS is used.
With the before mentioned steps i can reliably get the system to boot again and when it does it runs 100% stable, even with HT enabled.
Swapping out just the board also fixes the problem.
An i5 660 which also has HT but is a generation newer does also work fine, even with HT enabled.
Thank you for the additional information, it may seem repetitive but it does help those who are trying to give you possible answers. The obvious isn’t always to everyone and it is also easy to miss trivial things looking at the bigger picture.
The TDP is different, but doubtful that 20W would make or break the VRM, but then again TDP isn’t power draw so don’t assume the older i5 and i7 draw the same power either. So the biggest difference is going to be the generation, like others have mentioned, there could be an obscure feature missing from the older architecture but we’re still in the land of speculation.
At the end of the day you are talking about a chip that was manufactured more than half a decade before Win10 was released and it wouldn’t be unreasonable to assume that you might never be able to fix the problem because of the generation incompatibility. If reliability is the issue maybe it would be better to simply go with the newer i5. Sorry I don’t have a better solution, but I’m not certain that someone else will either unless they’ve come across this very problem themselves at some point.