The Problem with Super Micro Atom Chips and a Simple Fix

I recently encountered an issue with one of my Super Micro Atom chips, which is a common problem that seems to afflict many users of these systems. The chip in question had died on me while I was away on a mission, leaving me frustrated and looking for a solution. After some research, I discovered that the problem is due to the LPC (Low Pin Count) interface becoming worn out over time, which prevents the system from booting properly.

The LPC interface is used by the IPMI (Integrated Personnel Management Interface) onboard management interface to communicate with the operating system. To fix this issue, you need to pull the LPC pin to 3.3 volts. However, this will render the IPMI unable to communicate with the onboard operating system, which means that some of its features will be unavailable.

Fortunately, there is a simple solution to this problem. You can solder a 200 ohm resistor between pin 1 and pin 9 on the TPM (Trusted Platform Module) header. The TPM header has an LPC breakout, which makes it easy to access the chip. This fix essentially bypasses the worn-out LPC interface and allows the system to boot properly.

I had previously purchased one of these Atom chips and was initially disappointed when I encountered this issue. However, after researching the problem and finding a solution, I was able to get my system up and running again. The resistor fix may not be ideal, as it can interfere with the communication between the host system and the out-of-band management. Nevertheless, it's a simple and effective way to resolve the issue.

After some experimentation, I found that different resistance values worked for different chips. While 100 ohms was too small, resulting in an excessive current draw, and 600 ohms only worked for two of the three chips I tried, 200 ohms worked perfectly on one of them. The resistor I used is a through-hole resistor, which makes it easy to work with.

To achieve this fix, you'll need a wide pin header that has five pins and can be attached to the side opposite the notch. This will allow you to access the LPC breakout on the TPM header. You'll need to solder the 200 ohm resistor between pin 1 and pin 9 of the TPM header. This is a relatively simple process, but it does require some basic electronics knowledge.

I would like to note that I wouldn't recommend using these systems in production due to this issue. However, they make great home lab machines or for testing purposes. The resistor fix may not be suitable for long-term use, as it can affect the reliability of the system. Nevertheless, if you're looking for a quick and easy solution to resolve this issue, this might be worth considering.

In my experience, the Super Micro Atom chips are generally reliable systems that can last for a long time. However, this particular issue highlights the importance of maintaining your equipment and being prepared for potential problems. The resistor fix is a testament to the ingenuity of users who have encountered similar issues and found creative solutions.

"WEBVTTKind: captionsLanguage: enit's time for a level one diagnostic things are getting more claustrophobic here i've got a i've got a clean and that means purge and when i purge that's really when i get to the backlog of things that have been hanging around for a long time that i really probably should have fixed sooner so that is what has brought us today's level one diagnostic because if i don't fix it it's going in the dumpster and these are dead it's dead jim all right so these are pretty cool you know things to use as inexpensive edge routers and i say inexpensive uh these were around a thousand dollars when they were new in 2017-2018 this is an intel atom processor two or four cores typically four cores for the configurations that i work on it has eight gigabytes of uh dual channel error correcting memory it's got four on-board mix and a regular pci express by eight slot so you could have another four you could run you know a mirrored configuration for your uh operating system these make pretty awesome edge storage devices for caching and things like that because you've got a lot of sata connections you can put a lot of drives in here or edge routers or security appliances or anything custom like that you just need a a quick reliable linux box this is the model 505-2 from super micro and the motherboard is an a1s 2758f intel has screwed us all with the intel atom there's a there's an errata you can get a fix under warranty it's a pain in the ass and a lot of these are actually going out of warranty so you can pick these up at surplus for basically nothing you can still buy these new for like 500 but i'm not advocating that the newer more replacement gear is uh much much better uh but you can get these for on the order of 50 to 100 in the used surplus market especially doa ones or dead ones sometimes you get lucky and you find a dead one on ebay although people on ebay i don't necessarily recommend that but depending on what's available in your area surplus that kind of thing if you see these and it's dead i don't think you got screwed the fix is actually pretty easy although you give up some things let me explain there's a problem with these atom chips where the lpc the chip sort of wears over time and you need to pull the lpc pin to 3.3 volts or the system won't boot because that's how it boots the ipmi the onboard management interface uses the lpc interface to communicate with the operating system there's fix but the fix will render it impossible for the ipmi to talk to the onboard operating system you can still use the ipmi you can still remote into it you can turn it on and off remotely through the the out of band management the cool stuff you can do from the command line like reset the user accounts that kind of thing from linux that's not going to work anymore and the fix is to basically solder a 200 ohm resistor between pin 1 and pin 9 on the tpm header because the tpm header actually has that lpc breakout the pin to the cpu to break out that's the most convenient way to get at it on this motherboard now i had one of these die in the field in like 2019 and it was an away mission so it was super frustrating because i got it all configured and everything was good and it was a reconfiguration and a lot of the time these things are fine until you reboot them i was like okay i got the reconfiguration it's acting weird let's reboot it and now it's dead and it's like okay it's like two o'clock in the morning because that's how it goes on these things i don't want to deal with this whiskey tango foxtrot and then i was like oh yeah the atoms have that problem right and i think i found a post on the eev blog that was something like oh you just put 100 ohm resistor and there wasn't a guide for the super micro motherboard but there was a guide for i think a synology nas or something else that was based on the atom um c20 and so i was able to sort of work that out on the underside of the motherboard but more recently i tweeted and it was like hey does anybody else have this problem you know who wants to do this and 0x47df on twitter which is a sleepy duck pond appreciator at least that's what their their name is right now thank you very much they responded and said hey here's a picture of what i did they installed a 100 ohm 110 ohm resistor as well now 100 ohms is not a lot of resistance that works out to about 40 milliamps through the cpu that's maybe not the best so i experimented with these these three are dead all three of them and 600 ohms worked on two of them but not the third and the third one worked with a 200 ohm resistor so that's red red brown these are cheap loose tolerance uh i'm using a through hole instead of a surface mount because i can show you a quick easy thing to do you can get this one one wide pin header that's gonna be five pins big basically and it goes on the side opposite the notch toward the notch side what does that mean well let me explain with pictures and that's pretty much it for this level one diagnostic is basically you're going to use a resistor on the tpm header if you use too small of a resistance value it's harder on the hardware than it needs to be and it may shorten its lifetime if you use too big of a resistor it may work for a little while and then flake out honestly if you do this fix i would not use these in production but they make great home lab machines and that kind of thing the one that i barged in the field i sort of forgot about because it was you know like three o'clock in the morning and i was like oh thank goodness i could sleep and it ran continuously until it was finally replaced i think in like late 2020 so the resistor fix may be pretty good in terms of you know lasting a long time it just interferes with the communication between the host system and the out-of-band management just be aware of that but otherwise everything actually works and i don't really see that as a huge deal because you can still use the out-of-band management to turn it on and off i mean it's fine quick video quick fix if you're searching for that kind of thing for this particular super micro chassis well i'm three for three and well this is level one i'm signing out you can find me in the level one forums thanks eev blog and also random person on twitter youit's time for a level one diagnostic things are getting more claustrophobic here i've got a i've got a clean and that means purge and when i purge that's really when i get to the backlog of things that have been hanging around for a long time that i really probably should have fixed sooner so that is what has brought us today's level one diagnostic because if i don't fix it it's going in the dumpster and these are dead it's dead jim all right so these are pretty cool you know things to use as inexpensive edge routers and i say inexpensive uh these were around a thousand dollars when they were new in 2017-2018 this is an intel atom processor two or four cores typically four cores for the configurations that i work on it has eight gigabytes of uh dual channel error correcting memory it's got four on-board mix and a regular pci express by eight slot so you could have another four you could run you know a mirrored configuration for your uh operating system these make pretty awesome edge storage devices for caching and things like that because you've got a lot of sata connections you can put a lot of drives in here or edge routers or security appliances or anything custom like that you just need a a quick reliable linux box this is the model 505-2 from super micro and the motherboard is an a1s 2758f intel has screwed us all with the intel atom there's a there's an errata you can get a fix under warranty it's a pain in the ass and a lot of these are actually going out of warranty so you can pick these up at surplus for basically nothing you can still buy these new for like 500 but i'm not advocating that the newer more replacement gear is uh much much better uh but you can get these for on the order of 50 to 100 in the used surplus market especially doa ones or dead ones sometimes you get lucky and you find a dead one on ebay although people on ebay i don't necessarily recommend that but depending on what's available in your area surplus that kind of thing if you see these and it's dead i don't think you got screwed the fix is actually pretty easy although you give up some things let me explain there's a problem with these atom chips where the lpc the chip sort of wears over time and you need to pull the lpc pin to 3.3 volts or the system won't boot because that's how it boots the ipmi the onboard management interface uses the lpc interface to communicate with the operating system there's fix but the fix will render it impossible for the ipmi to talk to the onboard operating system you can still use the ipmi you can still remote into it you can turn it on and off remotely through the the out of band management the cool stuff you can do from the command line like reset the user accounts that kind of thing from linux that's not going to work anymore and the fix is to basically solder a 200 ohm resistor between pin 1 and pin 9 on the tpm header because the tpm header actually has that lpc breakout the pin to the cpu to break out that's the most convenient way to get at it on this motherboard now i had one of these die in the field in like 2019 and it was an away mission so it was super frustrating because i got it all configured and everything was good and it was a reconfiguration and a lot of the time these things are fine until you reboot them i was like okay i got the reconfiguration it's acting weird let's reboot it and now it's dead and it's like okay it's like two o'clock in the morning because that's how it goes on these things i don't want to deal with this whiskey tango foxtrot and then i was like oh yeah the atoms have that problem right and i think i found a post on the eev blog that was something like oh you just put 100 ohm resistor and there wasn't a guide for the super micro motherboard but there was a guide for i think a synology nas or something else that was based on the atom um c20 and so i was able to sort of work that out on the underside of the motherboard but more recently i tweeted and it was like hey does anybody else have this problem you know who wants to do this and 0x47df on twitter which is a sleepy duck pond appreciator at least that's what their their name is right now thank you very much they responded and said hey here's a picture of what i did they installed a 100 ohm 110 ohm resistor as well now 100 ohms is not a lot of resistance that works out to about 40 milliamps through the cpu that's maybe not the best so i experimented with these these three are dead all three of them and 600 ohms worked on two of them but not the third and the third one worked with a 200 ohm resistor so that's red red brown these are cheap loose tolerance uh i'm using a through hole instead of a surface mount because i can show you a quick easy thing to do you can get this one one wide pin header that's gonna be five pins big basically and it goes on the side opposite the notch toward the notch side what does that mean well let me explain with pictures and that's pretty much it for this level one diagnostic is basically you're going to use a resistor on the tpm header if you use too small of a resistance value it's harder on the hardware than it needs to be and it may shorten its lifetime if you use too big of a resistor it may work for a little while and then flake out honestly if you do this fix i would not use these in production but they make great home lab machines and that kind of thing the one that i barged in the field i sort of forgot about because it was you know like three o'clock in the morning and i was like oh thank goodness i could sleep and it ran continuously until it was finally replaced i think in like late 2020 so the resistor fix may be pretty good in terms of you know lasting a long time it just interferes with the communication between the host system and the out-of-band management just be aware of that but otherwise everything actually works and i don't really see that as a huge deal because you can still use the out-of-band management to turn it on and off i mean it's fine quick video quick fix if you're searching for that kind of thing for this particular super micro chassis well i'm three for three and well this is level one i'm signing out you can find me in the level one forums thanks eev blog and also random person on twitter you\n"