PCI-E lane question on Intel 690 motherboard with 12700k

Archaea

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I bought this motherboard
Gigabyte 690 Elite AX with DDR5
https://www.gigabyte.com/us/Motherboard/Z690-AORUS-ELITE-AX-rev-1x#kf

and an Intel 12700K


Here is the mothberboard block diagram.
1654974975266.png


here is the manual:
https://download.gigabyte.com/FileL...e_1101.pdf?v=c37d71474b557325ed5e5465e6099f74


My question is there are only 28 PCI-E Lanes on these Intel systems right? And four of those are shared with LOTs of things (USB/Wifi/Sata/Bluetooth/LAN -- etc?)

Labeled in Red:
(1) 16x for my 3080
(2) 4x (M2A_CPU) for my 1TB NVME SK Hynix P41 Windows 11 OS drive
(3) 4x for my 3.2TB Fusion IO PCI-E 4x Games storage card? (this is just a 4x physical card - not 16x)
1654975723810.png

1654975668496.png

(4) I'm using SATA port 7 for a 1TB SSD for extra storage which doesn't use any dedicated PCI-E lanes.

Does this mean I'm out of PCI-E Lanes? and if I plug anything else in, it would drop my video card to 8x?
I have a Western Digital Black NVME drive that I'd like to add (5), but not at the expense of 16x to 8x PCI-E lanes.

Also -- I'd just try this and experiment, but my case seems to be ever so slightly bent somehow, or maybe it's the video card instead, but whatever it is, getting my video card in and out of the motherboard is a real pain, and seems like it's going to damage something if I keep trying to do so.

1654975515688.png




This kind of information confuses me more:
1654975957056.png
 
That’s good to hear, but how does it even work? Does the 690 Chipset have its own PCI-E lanes in addition to what the CPU offers?

I.E.
lntel Ark site says that the 12700K only has 20 PCI-E lanes.
https://ark.intel.com/content/www/u...2700k-processor-25m-cache-up-to-5-00-ghz.html
The Z690 chipset is not connected directly to the CPU's PCI-E lanes per se - but is instead connected to the CPU's eight DMI lanes (in this case, DMI 4.0, which provides the maximum total bandwidth/throughput of eight PCI-E 4.0 lanes). The Z690 and H670 chipsets utilize all eight of those DMI 4.0 lanes; the B660 utilizes only four of those lanes. The budget H610 chipset also utilizes only four DMI lanes; however, it is throughput-limited at DMI level to DMI 3.0.

The Z690 chipset itself provides up to 28 additional PCI-E lanes, operating at up to PCI-E 4.0 spec. However, all 28 of those lanes share the exact same PCI-e 4.0 x8 throughput.
 
In addition to what E4g1e said, your board splits the 20 lanes this way: 16 5.0 lanes to the x16 slot and 4 4.0 lanes to the M.2 slot.
 
If you add an NVMe drive to a slot other then the one connected directly to the CPU it will go trough the chipset, unless you are connecting and using tons of devices on there at the same time you should not notice any difference in performance.
 
If you add an NVMe drive to a slot other then the one connected directly to the CPU it will go trough the chipset, unless you are connecting and using tons of devices on there at the same time you should not notice any difference in performance.
Yep, the chipset link is finally fast enough where you don't really have to worry too much about "it needs to use cpu lanes for performance reasons" anymore which is awesome.
 
That's so funny. I can't tell you how many times I cut/pasted/shared the Intel Core i7-12700K Expansion Options spec chart shown in Post No. 4 trying to get a handle on the very same thing; namely, why Intel chooses to hang the consumer out to dry when it comes to PCIe resources. I mean, seriously, the giant Vanguard-owned chip maker out of Santa Clara (aka, Intel) is forced by AMD to get off of the "quad-core" couch, after pulling down the big bucks for more than 10 years, to sprinkle in some added cores, but they make the conscious decision to cap the PCIe lane expansion option for consumers to "20"? If one were to look at Intel's i9-10980XE CPU, for example, they would clearly see that the chip company that loves "lakes," Intel, has known how to build plenty of cores (18) and plenty of PCIe lane support (48) into a CPU for quite some time now! That was a CPU that was launched nearly two-and-a-half freakin' years ago (late 2019)!

Anyway, I'm with you, Archaea , why should we have to worry about so-called "shared resources"? It's not like Intel isn't making plenty of money in the chip business.

By the way, need a geography lesson on North American lakes? All you need to do is look at the handy Intel Lake Guide:


Screen Shot 2022-06-30 at 3.14.13 PM.png
 
That's so funny. I can't tell you how many times I cut/pasted/shared the Intel Core i7-12700K Expansion Options spec chart shown in Post No. 4 trying to get a handle on the very same thing; namely, why Intel chooses to hang the consumer out to dry when it comes to PCIe resources. I mean, seriously, the giant Vanguard-owned chip maker out of Santa Clara (aka, Intel) is forced by AMD to get off of the "quad-core" couch, after pulling down the big bucks for more than 10 years, to sprinkle in some added cores, but they make the conscious decision to cap the PCIe lane expansion option for consumers to "20"? If one were to look at Intel's i9-10980XE CPU, for example, they would clearly see that the chip company that loves "lakes," Intel, has known how to build plenty of cores (18) and plenty of PCIe lane support (48) into a CPU for quite some time now! That was a CPU that was launched nearly two-and-a-half freakin' years ago (late 2019)!

Anyway, I'm with you, Archaea , why should we have to worry about so-called "shared resources"? It's not like Intel isn't making plenty of money in the chip business.

By the way, need a geography lesson on North American lakes? All you need to do is look at the handy Intel Lake Guide:


View attachment 487913
lol welcome to [H], seems youll fit in just fine :)
 
but they make the conscious decision to cap the PCIe lane expansion option for consumers to "20"?

Mayve that's because that is enough for 90%+ of all users, for those who want more there is the HEDT segment which needs something to feel different from the mainstream. Not that I would not like more lanes but i doubt there is a lot of demand for them and the DYI market is peanuts for intel anyways.
 
Sorry, but the consumer market is much bigger than described in this thread: and the post about Intel keeping expansion options down affects all consumer motherboard makers, not just the DIY segment...

Screen Shot 2022-07-06 at 12.34.06 AM.png


Thanks for the post and have a great day.
 
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Sorry, but the consumer market is much bigger than described in this thread: and the post about Intel keeping expansion options down affects all consumer motherboard makers, not just the DIY segment...
Not sure the point being made, most otf the Dell/Hp buyer have very little need for them (virtually 100% of the buyers does not) and those company have access to the Xeon segment (so are the Dell/Hp buyer) that will be sold has server or workstation if needed. It is very similar for those consumer PC maker to an DIY has a situation, not sure I grasp the difference.

One could say that the price hike got too big between regular and the high pci lane count for Amd/Intel, but at least for Amd for a while they had issue make enough for the demand on the high priced part and even if it is not that many actual lane having say 24 of PCI 5.0 is a giant amount of bandwith that could mean loosing half of it on the video card a non issue and offering more than enough say hard drive bandwith, a single PCI 5.0 drive would be a giant amount, no need for complex raid type of solution I could imagine for most.
 
That's so funny. I can't tell you how many times I cut/pasted/shared the Intel Core i7-12700K Expansion Options spec chart shown in Post No. 4 trying to get a handle on the very same thing; namely, why Intel chooses to hang the consumer out to dry when it comes to PCIe resources. I mean, seriously, the giant Vanguard-owned chip maker out of Santa Clara (aka, Intel) is forced by AMD to get off of the "quad-core" couch, after pulling down the big bucks for more than 10 years, to sprinkle in some added cores, but they make the conscious decision to cap the PCIe lane expansion option for consumers to "20"? If one were to look at Intel's i9-10980XE CPU, for example, they would clearly see that the chip company that loves "lakes," Intel, has known how to build plenty of cores (18) and plenty of PCIe lane support (48) into a CPU for quite some time now! That was a CPU that was launched nearly two-and-a-half freakin' years ago (late 2019)!

Anyway, I'm with you, Archaea , why should we have to worry about so-called "shared resources"? It's not like Intel isn't making plenty of money in the chip business.

By the way, need a geography lesson on North American lakes? All you need to do is look at the handy Intel Lake Guide:


View attachment 487913
It's because mainstream Intel CPU's are cut out of mobile silicon where having extra I/O is a detriment (it adds cost, increases the pin count, and generally does nothing useful in laptops). Frankly the reason why mainstream Intel is so good for gaming is exactly because the design is *not scalable* - it keeps latencies down which is important for applications like games where there is a ton of interprocess communication.

HEDT gets you the I/O you want, but in order to support 64+ lanes and 8 memory channels the internal layout of the chip gets rearchitected which makes applications that don't need those lanes and channels...perform worse.
 
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