Linux - HardwareThis forum is for Hardware issues.
Having trouble installing a piece of hardware? Want to know if that peripheral is compatible with Linux?
Notices
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Get a virtual cloud desktop with the Linux distro that you want in less than five minutes with Shells! With over 10 pre-installed distros to choose from, the worry-free installation life is here! Whether you are a digital nomad or just looking for flexibility, Shells can put your Linux machine on the device that you want to use.
Exclusive for LQ members, get up to 45% off per month. Click here for more info.
Does anyone know what happens when a person installs more RAM in a machine than the manufacturer says is allowed?
We had a system board go out on a ten year old Dell SC1430 server recently. I found a new system board for it for $20 on eBay. In the process of that, I discovered that if that new system board fixes the machine, I could upgrade its processors from one 1.86 GHz Dual Core Xeon Processor, to two 3.00 GHz Quad Core Xeon Processors for another $25, plus maybe around $12 for another heat sink.
But the RAM would still be a little anemic. This server is only supposed to take a maximum of 8 GB RAM. I'm pretty sure I have some unused RAM laying around here that would fit in that machine. Does anyone have any idea what would happen if I were to drop 16 GB RAM into it?
I'd like to get this machine running again. I don't really want to break it even worse in the process.
Any feedback, knowledge or experience with this would be appreciated!
it does not get used, because it will not recognize anything over max size set inside of BIOS
My motherboard with the CPU I am using can get up to 32GB ram but my BIOS will only recognize RAM up to 16GB
(laptop)
CPU: Intel i7-2760QM (8) @ 3.500
as far as just slapping that RAM into it then turning it on _ i do not think anything will blow up, mine didn't. as once I got the wrong type RAM and all it did was not work, so I pulled it, and got the right one the second time,
as far as you goes, as long as it is the right type RAM - regardless of capacity, it will either see it then use it or not see it and therefore not boot, or it will see only the MAX amount it is set to see and not use all of it
As long as it's the right type of memory, it should work fine. When the manufacturer says it has a max memory, that may be the chips that were available from the manufacturer itself (or in general) at the time of manufacture. There are exceptions though... I think FB-DIMMs do have an upper limit, but they have fallen out of favor as too slow and too expensive and haven't really been used in years.
It probably wouldn't be recommended for a mission-critical computer -- best to buy one that specifically says it supports that amount of memory.
However, most modern 64-bit processors use a 48-bit address space which is about 256 terabytes (exactly 256 tebibytes) . The way they implement it though, it can easily be changed to use the entire 64-bit address space and maintain backward compatibility with existing software (now, if you construct a pointer to the "dead zone" then try to access it, the processor immediately throws an exception and your computer crashes). That would boost the maximum RAM to about 16 exabytes (exactly 16 exbibytes) of physical RAM.
So anyway, all current x86_64 processors have 48-bits of wired address space, so you can only have 256 tebibytes of RAM. If you have that laying about, you should be able to fit it into your computer if it has enough RAM slots to hold it.
On the other hand some IBM mainframe processors and Sun/ORACLE UltraSPARC processors already have a full 64-bit address space.
As far as BIOS goes, most computers are UEFI/EFI now and even if they are actually BIOS (not emulated by UEFI/EFI), BIOS pretty much goes away when a modern operating system loads. It takes full control of the computer and doesn't have to go through BIOS which is only used for booting. As soon as UEFI/EFI takes over, you should have access to all memory installed no matter what the BIOS says.
Exceeding max RAM can do a few things. Rarely its failure to boot, mostly just the BIOS/UEFI and OS 'seeing' less RAM than installed.
Max RAM is set by the memory controller, either on the chipset (older systems) or the CPU (newer systems).
Thats why you'll see some rather complex 'Max RAM' sepcs on things like Intel LGA 2011-3 systems which have the memopry controller on the CPU, as they support both i7 (though IMO not a normal desktop i7) and Xeon CPUs.
Example- Asrock X99 OC Formula
Quote:
Memory - Quad Channel DDR4 Memory Technology
- 8 x DDR4 DIMM Slots
- Supports DDR4 3400+(OC)*/2933(OC)/2800(OC)/2400(OC)/2133 non-ECC, un-buffered memory
- Supports non-ECC x8 (8 bit) RDIMM (Registered DIMM)/x8 (8 bit) UDIMM
- Supports DDR4 ECC x8 (8 bit) RDIMM/x8 (8 bit) UDIMM with Intel® Xeon® processors E5 series in the LGA 2011-3 Socket, but not include x4 (4 bit) RDIMM/ x4 (4 bit) UDIMM.
- Max. capacity of system memory: 128GB (with Core™ i7 CPU) or 256GB (With Xeon® CPU)
- Supports Intel® Extreme Memory Profile (XMP) 2.0
When the manufacturer says it has a max memory, that may be the chips that were available from the manufacturer itself (or in general) at the time of manufacture.
Nope.
There has been single stick 32GB DDR3 RAM ECC commercially available since...err...2012 at the latest. 32GB and 16GB single sticks non-ECC have been around for a while.
But even though they are around, the max DDR3 RAM for current, normal desktop CPUs is 32GB to 64GB in total. Even on systems with 4 slots.
Quote:
Originally Posted by Laserbeak
As far as BIOS goes, most computers are UEFI/EFI now and even if they are actually BIOS (not emulated by UEFI/EFI), BIOS pretty much goes away when a modern operating system loads. It takes full control of the computer and doesn't have to go through BIOS which is only used for booting. As soon as UEFI/EFI takes over, you should have access to all memory installed no matter what the BIOS says.
Nope.
UEFI is not magic and will not change the max RAM for memory controller.
Quote:
Originally Posted by Br. Nicholas
We had a system board go out on a ten year old Dell SC1430 server recently. I found a new system board for it for $20 on eBay. In the process of that, I discovered that if that new system board fixes the machine, I could upgrade its processors from one 1.86 GHz Dual Core Xeon Processor, to two 3.00 GHz Quad Core Xeon Processors for another $25, plus maybe around $12 for another heat sink.
I'd be careful about exactly which CPUs you are looking at. The Dell datasheet isn't exactly information rich buit it does say this-
Quote:
Processors
Up to two Quad-Core Intel Xeon 5300 sequence processors at up to 1.86GHz;
Up to two Dual-Core Intel Xeon 5100 sequence processors at up to 2.33GHz;
Up to two Dual-Core Intel Xeon 5000 sequence processors at up to 3.0GHz
Front Side Bus
Intel Xeon 5300 Sequence: Dual Independent 1066MHz;
Intel Xeon 5100 Sequence: Dual Independent 1066MHz or 1333MHz;
Intel Xeon 5000 Sequence: Dual Independent 667MHz
5100 and 5300 series Xeons are Core based. 5100 are dual core, 5300 are quad core.
5000 series Xeons are Netburst (pentuim 4) based and dual core.
Its possible I'm missing something, or that Del have made some mistake, but according to that datasheet you can only hit 3.0 GHz with the dual core 5000 series.
If the datasheet is correct, the fastest setup you can get on those systems is going to be the 1.86GHz 5300 series (probably a Xeon E5320). Now its possible that datasheet was published and then Dell did some playing around with the BIOS and CPU support and a 3.0GHz Xeon (probably a X5365) will run, but thats a 1333MHz front side bus model, which should not be allowed. They are also 150 watt TDP model, the 1.86GHz E5320 is only an 80 watt TDP. The allowed 5000 series Xeons are in a similar TDP range a 95 watts. There are higher clocked 5000 series, up to 3733MHz but they are all 130 watt TDP models as well.
So I'd guess that aside from a few 'why cant that work' Xeon CPUs like the 5100 series like the 5160 (3GHz, 1333 FSB, 80 watt TDP, released the same day as the other 5100 series CPUs) it seems to sort of make sense. Maybe Dell locked out the 'top end' CPUs for a higher cost system? No idea.
You might be thinking 'hey, 3.0 GHz has got to be better than 2.33GHz or 1.86GHz.....' and you'd be wrong.
The slowest systems will be the 5000 series. Even if they have a higher clock speed.
Don't forget that Intel replaced the high clocked P4s with the lower clocked but faster, and much more efficient Core systems.
Considering how old the systems are, the only reason I'd replace them with something else that old is because you want/need EEC RAM or the RAID system. A newer system would pay for the increased overlay over time in lower power usage.
Who hasn't had problems with ram that should be OK on a system?? Many boards have a list of known working models that are stable. I recommend that you choose from that list of known stable or you run a risk. Once memory goes bad then you can never trust any of the data that gets written to drives.
Who hasn't had problems with ram that should be OK on a system?? Many boards have a list of known working models that are stable. I recommend that you choose from that list of known stable or you run a risk. Once memory goes bad then you can never trust any of the data that gets written to drives.
Yes. I know.
When I was putting together a purchase order for a new Solaris server to run ORACLE, it was determined by everyone that ORACLE was a mission-critical application so we had to buy ALL Sun-branded products including all the memory and hard drives even though they could be bought from reputable memory and disk manufactures for a mere fraction of the price. That's what really jacked up the price of the server, plus a redundant Sun power supply, etc.
UPDATE: First of all, I'd like to thank all of you for your very kind and helpful responses. I greatly appreciate it.
The new system board arrived late yesterday afternoon, so I installed it first thing this morning. I initially put 4GB of RAM in it, with its original processor. After I got that all configured and running, I ran a full set of diagnostics on it, and thank God, that all went well.
It turns out that I didn't have spare RAM for this that would take it above 8 GB, so I borrowed some from another server, and tried it, just to see what it would do. BIOS recognized all 16 GB just fine. It passed one complete set of Memtest just fine, too.
Unfortunately, the system event log showed some errors from one of the DIMMs, but in looking at the system event log on the server the RAM came from, it'd been throwing errors on it, too, but I just wasn't aware of it. So, it was kind of good to discover that before I tried to use that other server for something mission critical.
So since it looks like it's probably going to work, I'm going to buy some RAM for this machine, test it to no end, and see how it goes.
As far as the processor upgrade is concerned, I opted to buy a pair of Xeon E5450 processors, even though they are not officially supported for this system board. I think they're worth a try, and I have a good feeling about them, for what that is worth. They have not arrived yet, but I'll let you know how that goes once they're in, and the RAM is in, and everything is thoroughly tested.
That probably won't be until next week. Let's hope it doesn't turn into a 4th of July fireworks show!
But in any case, I really appreciate all of your kind responses. Jeremy has told me several times through the years that I'm one of the first 200 people to have signed up for LQ, and I've always found its forums to be some of the friendliest and most helpful forums on the net -- and I appreciate that! So thanks again!
Exceeding max RAM can do a few things. Rarely its failure to boot, mostly just the BIOS/UEFI and OS 'seeing' less RAM than installed.
Max RAM is set by the memory controller, either on the chipset (older systems) or the CPU (newer systems).
Thats why you'll see some rather complex 'Max RAM' sepcs on things like Intel LGA 2011-3 systems which have the memopry controller on the CPU, as they support both i7 (though IMO not a normal desktop i7) and Xeon CPUs.
There has been single stick 32GB DDR3 RAM ECC commercially available since...err...2012 at the latest. 32GB and 16GB single sticks non-ECC have been around for a while.
But even though they are around, the max DDR3 RAM for current, normal desktop CPUs is 32GB to 64GB in total. Even on systems with 4 slots.
Nope.
UEFI is not magic and will not change the max RAM for memory controller.
I'd be careful about exactly which CPUs you are looking at. The Dell datasheet isn't exactly information rich buit it does say this-
5100 and 5300 series Xeons are Core based. 5100 are dual core, 5300 are quad core.
5000 series Xeons are Netburst (pentuim 4) based and dual core.
Its possible I'm missing something, or that Del have made some mistake, but according to that datasheet you can only hit 3.0 GHz with the dual core 5000 series.
If the datasheet is correct, the fastest setup you can get on those systems is going to be the 1.86GHz 5300 series (probably a Xeon E5320). Now its possible that datasheet was published and then Dell did some playing around with the BIOS and CPU support and a 3.0GHz Xeon (probably a X5365) will run, but thats a 1333MHz front side bus model, which should not be allowed. They are also 150 watt TDP model, the 1.86GHz E5320 is only an 80 watt TDP. The allowed 5000 series Xeons are in a similar TDP range a 95 watts. There are higher clocked 5000 series, up to 3733MHz but they are all 130 watt TDP models as well.
So I'd guess that aside from a few 'why cant that work' Xeon CPUs like the 5100 series like the 5160 (3GHz, 1333 FSB, 80 watt TDP, released the same day as the other 5100 series CPUs) it seems to sort of make sense. Maybe Dell locked out the 'top end' CPUs for a higher cost system? No idea.
You might be thinking 'hey, 3.0 GHz has got to be better than 2.33GHz or 1.86GHz.....' and you'd be wrong.
The slowest systems will be the 5000 series. Even if they have a higher clock speed.
Don't forget that Intel replaced the high clocked P4s with the lower clocked but faster, and much more efficient Core systems.
Considering how old the systems are, the only reason I'd replace them with something else that old is because you want/need EEC RAM or the RAID system. A newer system would pay for the increased overlay over time in lower power usage.
I made a slight mistake in my post...BOTH BIOS and UEFI/EFI disappear once a modern OS is loaded. It is no longer needed. Try to get into BIOS/UEFI/EFI when booted into a modern OS.... it's impossible other than to perhaps change parameters for the next reboot. It is no longer relevant at all. The OS has has total control over the system. There is no running BIOS/UEFI/EFI or anything else but the OS itself.
Those things are just for booting.
Now more complex things like OpenBoot used in old PowerPC Macs and UltraSPARC Sun systems may be able to be accessible by stopping the running program (which is the OS itself), but I don't think that's applicable here. You can do something like that on an UltraSPARC Sun by typing (as root)
Code:
init 0
Then you should get an "ok" prompt which indicates you're talking to the hardware itself, no software is running.
LinuxQuestions.org is looking for people interested in writing
Editorials, Articles, Reviews, and more. If you'd like to contribute
content, let us know.
Installing RAM Greater than Maximum Allowed?
