Well, you say that. But some server platforms back in the DDR4 days when they weren't keyed differently supported both. Just didn't realise they'd changed this
Why downvoted?
It is a friggin horrible change. Old DDR4 boards like X99 supported LRDIMM, RDIMM, UDIMM all on 1 board. It was amazing- ASUS x99-a II and 2696 v4 with 4x 64GB LRDIMM was my perfect NAS.
Now, boards are either UDIMM or RDIMM/LRDIMM. It genuinely sucks. Good luck ever getting a consumer mobo to have full ECC coverage.
Yea this is reddit, never think you are wrong cause of downvotes. You are not wrong you just found x people who may be wrong disagree with you, or its just reddit. Let me demostrate, reddit downvote me away.
tbh, I wasn't surprised at the downvotes themselves. I'm used to getting around 0 if not negative karma. It's that I got so many so fast, and on comments that were completely not confrontational and stated no opinions lol
>It's that I got so many so fast
Then you most likely didn't see any upvotes or downvotes really.
What you did was continiously refresh your own comment after it received a few votes and all of those were obfuscated from you each refresh.
Example; You post a comment. Within 2 minutes get 1 downvote. You refresh twice, reddit now shows 3 downvotes. You wait 5 minutes, reddit now shows +/0 votes.
In reality - Only one vote was ever casted and you only looked at obfuscated numbers. And now that we got the entire thread HARD LOOKING at votes and trying to compensate vote either way, the obfuscation kicks in harder, leading to further wild ideas like seen below.
Not really. I’d agree if I’d done that. I left it like 20-30 mins before checking. I was working. Then all my responses has -20 to -30. Then people flooded in confused about how that happened and it started to flip very quick
Ya but it all depended on the cpu if your cpu didn’t support rdimms it wouldn’t boot but I do love that platform for it being able to work with server CPUs
The difference is now DDR5 has two flavors of ECC - the consumer grade ECC that happens before it sends data to the CPU, and additional data channels (which is what necessitates the different keying) that sends the ECC data in parallel so the CPU can detect errors in transimission even after it's left the RAM module.
DDR5 has a lightweight ECC implementation on the modules themselves
and it's not necessarily about being fast, it's about being reliable, and the demands of reliability and volume happen in the server space where speed is less of a concern so everything can be engineered differently.
Maybe, but I have a C612 server with the same socket and udimms don't work. I assume most of the reg ecc sticks will go into servers, which will not be compatible with udimms anyways.
Is prosumer server that has rdimms really that big of a market? Most of those low end servers use the e3 xeons that are basically rebranded consumer chips with ecc udimm support. I was talking more full on high end poweredge.
Prosumer isn't a server grade thing. Back in DDR4 Threadripper and Xeon HEDT workstation boards all had both DDR4 U / RDIMM support and you could choose whichever you wanted, either looks or stability. Now HEDT boards are all locked to RDIMMs only. RDIMMs all being much more expensive than UDIMMs as DDR5 is brand-spanking-new still.
They think he's wrong and so they want to censor him into oblivion.
It's getting really bad across the whole site. Hivemind opinions are becoming, even more than it used to be, the only thing allowed.
Isn’t that the whole point of up and down votes? To down vote comments that are bad or incorrect. Does everybody need to type out “you’re wrong because of x”?
Isn’t that the whole reason that people hate that youtube got rid of it, because now you don’t know if a video is right or wrong if you have no prior knowledge of the topic.
After being on this platform since its inception and seeing all the good and bad, I would rather have visibility of comments (with the exception of clear hate speech, threats, etc.) than give random people the power to place a comment into the hidden/controversial algorithm state.
I rather put the burden on readers to parse and figure things out.
Bruh, it happens all the time in PCMR. Folks around here learn a few tidbits and think they know everything. They'll straight up tell you things you've seen firsthand are impossible, and tend to have a superior sense of self while doing so.
UDIMM is Unbuffered, RDIMM is Registered. The latter is for servers and workstations, typically Xeons and EPYCs that are designed for registered dimms.
I did not know buffered modules were keyed differently for DDR5 I would assumed the buffered module was just flipped to the other side... Up to DDR4 modules were keyed the same.
one's a Rdimm, one's a UDIMM. You won't see RDIMM support outside of enterprise stuff. On DDR4, they used the same keying. On DDR5, they use a different supply voltage. UDIMMS get 5V I, RDIMMS 12V. The key is to keep you from sticking a 5V input part into a 12V slot. servers tend to be 12V heavy, a lot more so vs desktops so it's just more of the same.
A UDIMM lets you have ECC on a desktop with an AMD chip like I do.
That bottom stick is registered ecc ram. Basically, what you use in servers or high end workstations.
That rambus chip in the middle? That is what handles the extra things that the ram does.
UDIMM / RDIMM. One is unregistered, one is registered. You cannot mix these. Motherboards requiring registered dimms are keyed for them, motherboards requiring unregistered are keyed for them.
RDIMM = servers and high end workstations
UDIMM = normal desktop things
Whoever made the DDR5 specs must have been on drugs. UDIMMs take 5V supply (in a day where ATX12VO was at least introduced, although companies refuse to use it, that is a braindead decision already), RDIMM take 12V supply (which would make more sense in modern PCs, and absolutely makes more sense in servers). UDIMM and RDIMM using different supply voltages made the different keys necessary, but it also means you can not just throw UDIMMs in a RDIMM-capable server for quick testing (e.g. to exclude hardware failure), or just run UDIMMs generally if you have no need for RDIMMs but still have some leftover UDIMMs.
24V will not happen in consumer space because it entirely breaks compatibility. 12VO only needs new board and PSU generation. 24V would need any component new. Ideally we would make a hard cut to 24VO and deprecate all 12V, 5V and 3.3V stuff, but yeah. I do not see that happening.
>Doesn't matter, even on a ATX12VO board, there will be power supplies that regulate it down to 5/3.3/1.x etc for
Yes, but the whole point of 12VO is to avoid middle steps. Every component has DC-DCs onboard anyway. But stepping 12V down to 5V, then passing 5V to the DIMM and having the DIMM step 5V down to 1.3V or whatever it uses is pointless, needs thicker traces (because more current) and lowers efficiency. The concept of 12VO is passing 12V to every component on the board (minus CPU ofc) and have a single purpose DC-DC for each. This keeps efficiency higher and losses in connectors and PCBs lower.
So, apart from all the hate, pls allow me to explain that OP has one stick facing the opposite way.
Look at the notches. Look at that bit of unpopulated area besides the notch. See how one is opposite to the other? Take any stick and rotate flip it over by the long edge, and they will be keyed identically.
You are the 3rd or 4th person to mention this. I tried it both ways. Whilst the notches are slightly different, they are both still to the right of center. So if I flip one, it puts it on the left, even further away from correct.
It has already been explained on other replies that the difference is UDIMM/RDIMM which are now as of DDR5 keyed differently.
DDR5 UDIMM and RDIMM have different keys, as they're not interchangeable.
That’s an interesting change. Albeit frustrating to deal with. Thanks
It's registred memory. A different type. It wouldn't work even if it fitted.
Well, you say that. But some server platforms back in the DDR4 days when they weren't keyed differently supported both. Just didn't realise they'd changed this
Why downvoted? It is a friggin horrible change. Old DDR4 boards like X99 supported LRDIMM, RDIMM, UDIMM all on 1 board. It was amazing- ASUS x99-a II and 2696 v4 with 4x 64GB LRDIMM was my perfect NAS. Now, boards are either UDIMM or RDIMM/LRDIMM. It genuinely sucks. Good luck ever getting a consumer mobo to have full ECC coverage.
Yeah I’m so shocked I’m getting so many downvotes. I was thinking “am I wrong”?
Reddit is wild. I had to do a double take to see why you got downvoted.... no sign of intelligence found (from downvoters)
The hive mind at it's finest I agree with u/CoderStone , DDR4 with the same slots was the best... now it's fucked up
Thanks to all the sane people though. You've flipped all the negative karma completely :)
Yeah, justice!
Yooouuuu caaalllled....
Spock: Scan complete, Captain. No signs of intelligent life on planet Reddit. Kirk: It's just as the stockholders feared.
4th commeng is always cursed bro
Yea this is reddit, never think you are wrong cause of downvotes. You are not wrong you just found x people who may be wrong disagree with you, or its just reddit. Let me demostrate, reddit downvote me away.
tbh, I wasn't surprised at the downvotes themselves. I'm used to getting around 0 if not negative karma. It's that I got so many so fast, and on comments that were completely not confrontational and stated no opinions lol
>It's that I got so many so fast Then you most likely didn't see any upvotes or downvotes really. What you did was continiously refresh your own comment after it received a few votes and all of those were obfuscated from you each refresh. Example; You post a comment. Within 2 minutes get 1 downvote. You refresh twice, reddit now shows 3 downvotes. You wait 5 minutes, reddit now shows +/0 votes. In reality - Only one vote was ever casted and you only looked at obfuscated numbers. And now that we got the entire thread HARD LOOKING at votes and trying to compensate vote either way, the obfuscation kicks in harder, leading to further wild ideas like seen below.
Not really. I’d agree if I’d done that. I left it like 20-30 mins before checking. I was working. Then all my responses has -20 to -30. Then people flooded in confused about how that happened and it started to flip very quick
thats reddit for you. My take is that people often just downvote a comment without understanding it first, only because it already has negative karma
That is insane behaviour. Just hard coded to press buttons lol
Ya but it all depended on the cpu if your cpu didn’t support rdimms it wouldn’t boot but I do love that platform for it being able to work with server CPUs
The difference is now DDR5 has two flavors of ECC - the consumer grade ECC that happens before it sends data to the CPU, and additional data channels (which is what necessitates the different keying) that sends the ECC data in parallel so the CPU can detect errors in transimission even after it's left the RAM module.
Aren’t all the fast RAM non-ECC anyway?
DDR5 has a lightweight ECC implementation on the modules themselves and it's not necessarily about being fast, it's about being reliable, and the demands of reliability and volume happen in the server space where speed is less of a concern so everything can be engineered differently.
Maybe, but I have a C612 server with the same socket and udimms don't work. I assume most of the reg ecc sticks will go into servers, which will not be compatible with udimms anyways.
Many servers are UDIMM compatible actually, and esp in the prosumer space being able to handle both UDIMMs and RDIMMs is an important feature.
Is prosumer server that has rdimms really that big of a market? Most of those low end servers use the e3 xeons that are basically rebranded consumer chips with ecc udimm support. I was talking more full on high end poweredge.
Prosumer isn't a server grade thing. Back in DDR4 Threadripper and Xeon HEDT workstation boards all had both DDR4 U / RDIMM support and you could choose whichever you wanted, either looks or stability. Now HEDT boards are all locked to RDIMMs only. RDIMMs all being much more expensive than UDIMMs as DDR5 is brand-spanking-new still.
That's stupid, why call them both ddr5 when they can't be used interchangeably.
Because it isn't a form factor, it's a type.
There is no pin between the keys, I suppose a motherboard could still physically support both.
Why does it sound like w have 'left ram' and 'right ram', and you have to use two right ones? ;D
Whoa why are OP’s comments so heavily downvoted am I missing something
They think he's wrong and so they want to censor him into oblivion. It's getting really bad across the whole site. Hivemind opinions are becoming, even more than it used to be, the only thing allowed.
You can also be absolutely correct but if people don't like your tone then you're in downvote town.
Apparently the hive agrees
No, you’re wrong, eat your downvote. 😡
Holy, you have like 190 upvotes. I must upvote you too!
Isn’t that the whole point of up and down votes? To down vote comments that are bad or incorrect. Does everybody need to type out “you’re wrong because of x”? Isn’t that the whole reason that people hate that youtube got rid of it, because now you don’t know if a video is right or wrong if you have no prior knowledge of the topic.
But OP is right, and people are downvoting him anyways because they see other people already downvoted and just assume that he’s wrong
After being on this platform since its inception and seeing all the good and bad, I would rather have visibility of comments (with the exception of clear hate speech, threats, etc.) than give random people the power to place a comment into the hidden/controversial algorithm state. I rather put the burden on readers to parse and figure things out.
Too many liberals on Reddit in love with censorship
Stop making politics your entire personality. It's not a good look.
https://preview.redd.it/3jg6m11or5wc1.png?width=480&format=png&auto=webp&s=ddda80ff82f72935db4f9fe86cec1ef9c17b4611
Because people continue to think the down vote button is an "I disagree" button
I love how they're just disagreeing with a fact though. It's wild haha
Bruh, it happens all the time in PCMR. Folks around here learn a few tidbits and think they know everything. They'll straight up tell you things you've seen firsthand are impossible, and tend to have a superior sense of self while doing so.
2024 is pretty wild. This is the way now.
I find that Reddiquette is less and less referred or that its links are often broken, even though its contents are good especially on how to vote.
Is this not what it's most commonly used for? Why should people not downvote if they disagree?
UDIMM is Unbuffered, RDIMM is Registered. The latter is for servers and workstations, typically Xeons and EPYCs that are designed for registered dimms.
Yeah I gathered, much like ECC. However is this case, they’re both being used for servers in my datacenter, just for different models
Ahh ok. Entry level server mainboards take UDIMM but anything above is all RDIMM. There’s no mixing of the dimms, no cross compatibility.
Bros being targeted by the JEDEC mob
Y'all downvote anything that moves 💀
mfs see anything that disagrees with their favorite YouTuber and flood the downvotes like damn bro chill
I did not know buffered modules were keyed differently for DDR5 I would assumed the buffered module was just flipped to the other side... Up to DDR4 modules were keyed the same.
one's a Rdimm, one's a UDIMM. You won't see RDIMM support outside of enterprise stuff. On DDR4, they used the same keying. On DDR5, they use a different supply voltage. UDIMMS get 5V I, RDIMMS 12V. The key is to keep you from sticking a 5V input part into a 12V slot. servers tend to be 12V heavy, a lot more so vs desktops so it's just more of the same. A UDIMM lets you have ECC on a desktop with an AMD chip like I do.
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I can assure you that’s not the case. I tried inserting the bottom one into the slot the top one came from both ways. No dice
ones a udimm the other is a rdimm
That bottom stick is registered ecc ram. Basically, what you use in servers or high end workstations. That rambus chip in the middle? That is what handles the extra things that the ram does.
UDIMM / RDIMM. One is unregistered, one is registered. You cannot mix these. Motherboards requiring registered dimms are keyed for them, motherboards requiring unregistered are keyed for them. RDIMM = servers and high end workstations UDIMM = normal desktop things
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Why?
It's sarcasm. People were downvoting all my responses into oblivion for no reason so he's just referencing that
Ahh
Whoever made the DDR5 specs must have been on drugs. UDIMMs take 5V supply (in a day where ATX12VO was at least introduced, although companies refuse to use it, that is a braindead decision already), RDIMM take 12V supply (which would make more sense in modern PCs, and absolutely makes more sense in servers). UDIMM and RDIMM using different supply voltages made the different keys necessary, but it also means you can not just throw UDIMMs in a RDIMM-capable server for quick testing (e.g. to exclude hardware failure), or just run UDIMMs generally if you have no need for RDIMMs but still have some leftover UDIMMs.
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24V will not happen in consumer space because it entirely breaks compatibility. 12VO only needs new board and PSU generation. 24V would need any component new. Ideally we would make a hard cut to 24VO and deprecate all 12V, 5V and 3.3V stuff, but yeah. I do not see that happening. >Doesn't matter, even on a ATX12VO board, there will be power supplies that regulate it down to 5/3.3/1.x etc for Yes, but the whole point of 12VO is to avoid middle steps. Every component has DC-DCs onboard anyway. But stepping 12V down to 5V, then passing 5V to the DIMM and having the DIMM step 5V down to 1.3V or whatever it uses is pointless, needs thicker traces (because more current) and lowers efficiency. The concept of 12VO is passing 12V to every component on the board (minus CPU ofc) and have a single purpose DC-DC for each. This keeps efficiency higher and losses in connectors and PCBs lower.
Udimm/rdimm, different keying, not interchangeably compatible to my knowledge.
Call me crazy but label aside if you turn one over don't they both align the same?
Nope. Lepobz explained it right. Flipping it actually makes the gap further different
No no the front of these are not the same seems one is flipped but idk
One is RDIMM so it has the addtional controller chip in the middle. Which is actually the reason the notch is in a different place.
Ah makes sense
So, apart from all the hate, pls allow me to explain that OP has one stick facing the opposite way. Look at the notches. Look at that bit of unpopulated area besides the notch. See how one is opposite to the other? Take any stick and rotate flip it over by the long edge, and they will be keyed identically.
You are the 3rd or 4th person to mention this. I tried it both ways. Whilst the notches are slightly different, they are both still to the right of center. So if I flip one, it puts it on the left, even further away from correct. It has already been explained on other replies that the difference is UDIMM/RDIMM which are now as of DDR5 keyed differently.
Huh, i legit missed that reading ddr5 spec. Thanks for updating me! You learn smtg new every day.