The Intel 12th Gen Core i9-12900K Review: Hybrid Performance Brings Hybrid Complexity
by Dr. Ian Cutress & Andrei Frumusanu on November 4, 2021 9:00 AM ESTCPU Benchmark Performance: DDR5 vs DDR4
Traditionally we test our memory settings at JEDEC specifications. JEDEC is the standards body that determines the requirements for each memory standard. In this case, the Core i9 supports the following aligning with those standards:
- DDR4-3200 CL22
- DDR5-4800B CL40*
There's an * next to the DDR5 for a couple of reasons. First, when asked, Intel stated that 4800A (CL34) was the official support, however since the technical documents have now been released, we've discovered that it is 4800B (CL40). Secondly, 4800B CL40 technically only applies to 1 module per 64-bit channel on the motherboard, and only when the motherboard has two 64-bit slots to begin with. We covered Intel's memory support variants in a previous article, and in this instance, we're using DDR5-4800B memory in our testing.
As explained in our SPEC section, DDR5 memory not only brings bandwidth improvements but also the increased number of channels (4x32-bit vs 2x64-bit) means that the memory can be better utilized as threads pile on the memory requests. So while we don't see much improvement in single threaded workloads, there are a number of multi-threaded workloads that would love the increased performance.
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ajollylife - Sunday, November 7, 2021 - link
I agree. I've got a 3995wx everything on qvl, even with an optane drive. Got too annoyed with the bugs and found a 5950x worked better for a high performance desktop. Going to swap to a 12900k once i can find parts.TheJian - Sunday, November 7, 2021 - link
If you know how to use mem timings, you idiots that depend on SPD's wouldn't have these problems (that covers about 90% of this crap, and knowing other bios settings solves almost anything else besides REAL failures). I've been building systems for decades (and owned a PC biz for 8yrs myself) and a MB's QVL list was barely used by anyone I know (perhaps to look up some ODD part but otherwise...Just not enough covered at launch etc). If I waited for my fav stuff to be included in each list I'd never build. Just buy top parts and you don't worry much about this crap.That said, if my job was on the line, I'd check the list, but not because I was worried about ever being wrong...LOL. I just don't have a liars face. I'd be laughing about how stupid I think it is after so many builds and seeing so many "incompatible memory" fixed in seconds in the hands of someone not afraid to disable the SPD and get to work (or hook up with a strap before blowing gigs of modules, nics repeatedly etc). Even mixing modules means nothing then (again, maybe if I was pitching servers...DUH....1 error can be millions) after just trying to make issues exists with mixing/matching but with timings CORRECT. No, they will work, if set correct barring some REAL electrical issue (like a PSU model from brand X frying a particular model mboard - say dozens in a weekend, a few myself!).
Too many DIY people out that that really have no business building a PC. No idea what ESD is (no just because it took a hit and still works doesn't mean it isn't damaged), A+ what?? Training? Pfft, it's just some screws and slots...Whatever...Said the guy with machine after machine that have never quite worked right...LOL. If you live in SF or some wet joint OK (leo leporte etc? still around), otherwise, just buy a dell/hp and call it a day. They exist because most of you are incapable of doing the job correctly, or god forbid troubleshooting ANYTHING that doesn't just WORK OOB.
Qasar - Sunday, November 7, 2021 - link
blah blah blah blah blahMidland_Dog - Saturday, November 27, 2021 - link
people like you cost amd salessilly amdumb
cyberpunx_r_ded - Friday, November 5, 2021 - link
sounds like a Mobo problem, not a CPU problem....for someone who has put together "hundreds of systems" you should know that by the symptoms.That motherboard is known to be dog sh1t btw.
DominionSeraph - Saturday, November 6, 2021 - link
Note Intel doesn't allow "dog sh1t motherboards" to happen, especially at the $300+ price point. That makes it an AMD issue.I can refurb Dell after Dell after Dell after Dell, all of them on low-end chipsets and still on the release BIOS, and they all work fabulously.
Meanwhile two years into x570 and AMD is still working on getting USB working right.
I think I'll put this thing on the market and see if I can recoup the better part of an i9 12900k build. I may have to drop down to one of the i7 6700's or the i7 4770k system I have until they're in stock, but that's really no issue.
Netmsm - Saturday, November 6, 2021 - link
It's a pleasure to not have p*gheaded amateurs in the AMD zone.Others are telling you it's not AMD issue but you spamming it's AMD, AMD, AMD... having got the wrong and of the stick.
Wrs - Saturday, November 6, 2021 - link
@Netmsm Regardless of whether the blame lies with ASRock for the above issue, it remains a fact that AMD didn't fix a USB connectivity problem in Zen 3 until 6-7 months after initial availability. Partly that was because the installed base of guinea pigs was constricted by limited product, but it goes to show that quick and widespread product rollouts have a better chance of ironing out the kinks. (Source if you've been under a rock heh https://www.anandtech.com/show/16554/amd-set-to-ro...And then recently we had Windows 11 performance regressions with Zen 3 cache and sandboxed security. These user experience hiccups suggest one company perceptibly lags the other in platform support. It's just something I've noticed switching between Intel and AMD. I might think this all to be normal were I loyal to one platform.
Netmsm - Sunday, November 7, 2021 - link
I didn't realize we're here to discuss minor issues/incompatibilities of the Intel's rival. I thought we're here to talk about major inefficiencies besides improvements of Intel's new architecture. Sorry!Wrs - Sunday, November 7, 2021 - link
@Netmsm That's no minor issue/incompatibility. Maybe for you, but a USB dropout is not trivial! Think missing keystrokes, stuttering audio for USB headsets and capture cards. It didn't affect every user, and was intermittent, which was part of the difficulty. I put off a Ryzen 5000 purchase for 2 months waiting for them to fix it. (I also put it off for 4 months before that because of lack of stock lol.)