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 Tests: SPEC MT Performance - DDR5 Advantage
Multi-threaded performance is where things become very interesting for Alder Lake, where the chip can now combine its 8 P-cores with its 8 E-cores. As we saw, the 8 E-cores are nothing to sneeze about, but another larger consideration for MT performance is DDR5. While in the ST results we didn’t see much change in the performance of the cores, in MT scenarios when all cores are hammering the memory, having double the memory channels as well as +50% more bandwidth is going to be extremely beneficial for Alder Lake.
As we noted, the DDR5 vs DDR4 results showcase a very large performance gap between the two memory technologies in MT scenarios. Running a total of 24 threads, 16 for the SMT-enabled P-cores, and 8 for the E-cores, Alder Lake is able to take the performance crown in quite a lot of the workloads. There are still cases where AMD’s 16-core setup with larger cores are able to perform better, undoubtedly also partly attributed to 64MB of on-chip cache.
Compared to the 11900K, the new 12900K showcases giant leaps, especially when paired with DDR5.
In the FP suite, the DDR5 advantage in some workloads is even larger, as the results scale beyond that of the pure theoretical +50% bandwidth improvement. What’s important for performance is not just the theoretical bandwidth, but the actual utilised bandwidth, and again, the doubled up memory channels of DDR5 here are seemingly contributing to extremely large increases, if the workload can take advantage of it.
In the aggregate results, there’s very clearly two conclusions, depending on whether you use the chip with DDR5 or DDR4.
With DDR4, Alder Lake and the 12900K in particular, is able to showcase very good and solid increases in performance, thanks to the IPC gains on the Golden Cove core, but most importantly, also thanks to the extra 8 Gracemont cores, which do carry their own weight. The 12900K falls behind AMD’s 5900X with DDR4, which is fair given the pricing of the chips here are generally in line with teach other.
With DDR5, the 12900K is able to fully stretch its multi-threaded performance legs. In less memory dependent workloads, the chip battles it out with AMD’s 16-core 5950X, winning some workloads, losing some others. In more memory dependent workloads, the DDR5 advantage is extremely clear, and the 12900K is able to blow past any competition, even slightly edging out the latest Apple M1 Max, released a few weeks ago, and notable for its memory bandwidth.
Facebook
Twitter
RSS
474 Comments
View All Comments
Netmsm - Monday, November 8, 2021 - link
@Wrs Assume we give you this, just drop AMD related things.Let's focus on performance per watt of new Intel Architecture. I asked some questions about this which is a pertinent topic to this article but you dodged. Just talk about 241 watt being sucked by 12900k :))
ajollylife - Sunday, November 7, 2021 - link
To be fair Intel's def not perfect. The i225v lan bug comes to mindDominionSeraph - Saturday, November 6, 2021 - link
When Intel doesn't have this issue it is AMD.Intel demands validation and spends hundreds of millions on engineers to help motherboard manufacturers fix their issues before release because they realize that the motherboard is an INSEPERABLE part of the equation. You can fanboi all you want over the CPU, but if there are no good motherboards you have a terrible system.
AMD just dumps their chip on the market, leaving the end-user with a minefield of motherboard issues among every manufacturer.
When Intel has the problem solved but AMD doesn't, it's an AMD issue.
Qasar - Saturday, November 6, 2021 - link
DominionSeraph have you tried this on a different x570 board ? it COULD be just that board, as was already stated. i have been running a 5900x now for about a week, and no issues at all with disk access, its the same as the 3900x i replaced, and im using an asus x570 e-gaming board.maybe take a step back, realize that its NOT an amd issue, but a BOARD issue. to be fair, intel has had its own issues over the years as well, while you see them as perfect, sorry to break it to you, but intel also isnt perfect
Netmsm - Sunday, November 7, 2021 - link
Oh I got it, the fact that you're encountering unusual issues, despite myriads of people who haven't complained of the same problem you have, means that AMD got many incompatibility issues.That's a brilliant reasoning which brings us to a pure conclusion: AMD is bad. We're done here.
Dug - Monday, November 15, 2021 - link
@DominionSeraph"Note Intel doesn't allow "dog sh1t motherboards" to happen, especially at the $300+ price point. That makes it an AMD issue."
You obviously haven't looked at or experienced the issues that plague many motherboards. Maybe just read some reviews or visit manufactures forums to get an idea of how bad it is before making such a naïve statement.
It has more to do with the manufacturer of the board than the CPU.
That is like saying nvidia doesn't make crap video cards. Well you need to look at all the failures by each manufacturer, not nvidia itself.
madseven7 - Saturday, November 6, 2021 - link
You put that chip in an ASROCK motherboard. That's the reason for the issues.xhris4747 - Tuesday, November 9, 2021 - link
Lol 😅FLORIDAMAN85 - Friday, November 12, 2021 - link
I, too, have made the error of purchasing an ASRock board.mode_13h - Saturday, November 13, 2021 - link
So far, my ASRock Rack server board is still going strong.