Intels new HEDT (LGA 2066, Skylake-X, Kaby Lake-X)

Kaotik

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So, Intel revealed at Computex their new LGA 2066 -platform and CPUs to accompany it.
And it's a mess.

Kaby Lake-X are the exact same as Kaby Lakes only fitted for LGA 2066 instead of LGA 1151, and iGPU fused off (but still on silicon).
They support 2 memory channels, so 2-4 slots (depending on if the motherboard has 4 or 8 slots) per motherboard apparently won't work at all.
They support 16 PCIe lanes, so some of the PCIe slots won't apparently work either.

Skylake-X is split into two: LCC aka Low Core Count and HCC aka High Core Count.
LCC's are 6 to 12 cores, 4 memory channels and 28 PCIe lanes for 6- and 8-core models, 44 for 10- and 12-cores. Intel hasn't specified 12-core versions clocks, caches or TDP yet. Intel hasn't specified release dates for all of the models yet apparently either (6-10 cores Q2, no word about 12-core)
HCC's are 14 to 18 cores, 4 memory channels and 44 PCIe lanes. Intel hasn't specified any clocks, TDP, release dates or anything for any of the models yet. Asus rep slipped that 18-core version won't actually be even released until next year. edit: ASUS rep has edited his post to say "later this year" instead. https://rog.asus.com/forum/showthread.php?93632-Late-June&p=653561&viewfull=1#post653561

LGA 2066 platform has great new feature: Bootable NVMe RAID from the CPU.
Except that it's only RAID 0 by default. Getting RAID 1 and 10 means you have to buy physical key which costs $99. Getting RAID 5 means getting another physical key which costs around $300. And you actually need Intel-branded NVMe SSDs for it to work at all.

Video with lot of the same info:

edit: fixed small mistakes I made tired last night
 
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If you buy a motherboard with Intel's latest chipset (X299) and a CPU with Intel's latest CPU architecture (Kaby Lake) and then buy 8 sticks of RAM, half of the RAM will be unavailable.
And to top this, if you fill out the PCI-Express slots with 2 high-end graphics cards + soundcard + NVMe solution, there's a large chance a couple of those won't even work.


This will be entertaining to watch.
 
KabyLake-X HEDT has only dual channel memory controller, but uses same motherboards as Skylake-X HEDT. These motherboards are designed for quad channel memory. Half of the memory slots are disabled in dual channel mode, meaning that you need to buy fewer & bigger memory chips for KabyLake-X. And you can't equip as much memory as other HEDT chips.
 
Half of the memory slots are disabled in dual channel mode,
thanks that narrows it down a bit but why are half the slots disabled
Surely the thing to do is if the board has 8 slots but the cpu only supports dual channel memory run the 8 slots in dual channel mode 4x2
If the cpu has a quad channel controller run 8 slots in 2x4, why do they need to be disabled ?
unless the dual channel cpu's for some reason only support a maximum of 4 slots ?
 
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That's how it goes, CPUs support two DIMM per channel, or three DIMMs per channel if using registered memory and the latter isn't supported on consumer CPU nor even Xeon E3 either.

And with three DIMMs per channel (e.g. you have single socket 2011-3 motherboards with twelve slots able to support a truly big amount of memory) you even have an official speed restriction e.g. on Haswell E5 Xeon, you drop down to DDR4 1866 plus the small performance penalty from using registered memory.
 
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That's how it goes, CPUs support two DIMM per channel,
and only 2 channels ?
and if thats the case if you have a cpu that supports 4 dimms per channel and only put in 2 dimms doesnt it run in dual channel
so if intel make all the new cpu's support 4 dimms per channel that would solve the problem of unusable slots yes ?
 
and only 2 channels ?
and if thats the case if you have a cpu that supports 4 dimms per channel and only put in 2 dimms doesnt it run in dual channel
so if intel make all the new cpu's support 4 dimms per channel that would solve the problem of unusable slots yes ?
Motherboards assign certain slots to certain channels
X299 has Channels 0/1/2/3 and 1 or 2 slots for each channel (depending on if there's 4 or 8 slots total).
With Kaby Lake-X you can fill Channel 0 & 1 slots, with Skylake-X you can fill all 4 channels.

Z170 has Channels 0/1 and 1 or 2 slots for each channel (depending on if there's 2 or 4 slots total).
If you put all your DIMMs in Channel 0 or 1 you'll run in single channel mode, if you put DIMMs in both channel slots you'll run dual channel mode.
(and same for X299, if you have 8 slots and put in only 2 DIMMs and place them both in Channel 0 slots, you'll run in single channel mode etc)
 
the way you explain it kaotik
its not about x299
kabylake only supports 4 dimms while skylake supports 8 - yes ?
 
the way you explain it kaotik
its not about x299
kabylake only supports 4 dimms while skylake supports 8 - yes ?
They both support 2 DIMMs per channel, so 4 and 8, but it's also about the motherboard - the motherboard has 4 channels and 1 or 2 slots per channel, with Kaby Lake-X half of the slots simply won't work
 
which means Kaby-X only supports 2 channels - yes ?
2 channels, 2 slots per channel = 4 dimms - yes ?

If the motherboard has 8 slots, then yes. However, since you lose quite a lot of ram speed at the top end if you use two dimms per channel, some quad channel motherboards in the past have only had a single slot per channel. On such a motherboard and with a Kaby-X, only 2 of the memory slots are usable.
 
which means Kaby-X only supports 2 channels - yes ?
2 channels, 2 slots per channel = 4 dimms - yes ?
as @tunafish said, 4 dimms if the motherboard has 8 slots. If the motherboard has 4 slots, you only have 1 slot per channel and thus can use only 2 dimms on kaby-x
 
hang on if you only had 1 slot per channel then you'd have a cpu running single channel memory no one would make a motherboard like that
 
hang on if you only had 1 slot per channel then you'd have a cpu running single channel memory no one would make a motherboard like that
Now you see the frustration that the motherboard makers have with this platform.
 
hang on if you only had 1 slot per channel then you'd have a cpu running single channel memory no one would make a motherboard like that
No you wouldn't, you could have dual channel with Kaby Lake-X (channels 0 & 1) and quad channel with Skylake-X (channels 0, 1, 2 & 3)
Motherboard designed for 2 memory channels and 4 slots (for example Z270+Kaby Lake):
Channel 0 | Channel 0 | Channel 1 | Channel 1 (this is why with 2 DIMMs you leave 1 slot in between them - also there could be mobos where it goes 0101 but they're rare these days, if not extinct)
Motherboard designed for 4 memory channnels and 4 slots (for example X299 with 4 slots)
Channel 0 | Channel 1 | Channel 2 | Channel 3
Motherboard designed for 4 memory channnels and 8 slots (for example X299 with 8 slots)
Channel 0 | Channel 1 | Channel 2 | Channel 3 | Channel 0 | Channel 1 | Channel 2 | Channel 3

Kaby Lake-X can use channels 0 and 1, Skylake-X channels 0, 1, 2 and 3
 
If the motherboard has 4 slots, you only have 1 slot per channel and thus can use only 2 dimms on kaby-x
which you are now contradicting with your quote below see why im getting confused

Motherboard designed for 2 memory channels and 4 slots (for example Z270+Kaby Lake):
Channel 0 | Channel 0 | Channel 1 | Channel 1 (this is why with 2 DIMMs you leave 1 slot in between them
Motherboard designed for 4 memory channnels and 4 slots (for example X299 with 4 slots)
Channel 0 | Channel 1 | Channel 2 | Channel 3
 
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