X299 dual channel vs. quad channel RAM

[batboy]

On X299 MBs, if you have a X-series CPU with 4 cores or less, you are forced to run dual channel. With 6 cores or more, it switches to quad channel. How does it know? How does it switch? Surely some smart fellow can figure out how to trick the motherboard into activating quad channel? Is there white papers we can look at or something?

 

[TimoneX]

Uh no, that won't work. The Integrated Memory Controller is on the CPU itself. Chipsets are now largely relegated to what we old timers would have called a Southbridge back in the day.

 

[batboy]

Was not exactly what I wanted to hear, but I figured someone here knew.

 

[TimoneX]

Yeah, it would've been fun. I recall a dual socket 370? motherboard from Abit that had an out-of-box hack that let you run two celeries in SMP. My gosh I must have had 3 or 4 of those beauties over the years...what a fun motherboard that was.

 

[mackerel]

Abit BP6? http://www.anandtech.com/show/343
So old Anand was still at Anandtech!

Had one as my first multi-anything system. fsb overclock to 560-ish.

 

[TimoneX]

That's the critter. Man that thing was a wicked good value with a couple celerons seated upon it.

 

[EarthDog]

On X299 MBs, if you have a X-series CPU with 4 cores or less, you are forced to run dual channel. With 6 cores or more, it switches to quad channel. How does it know? How does it switch? Surely some smart fellow can figure out how to trick the motherboard into activating quad channel? Is there white papers we can look at or something?

No.

The number of channels comes from the CPU and its IMC (Integrated Memory Controller).

 

[Dolk]

Blip.

 

[TimoneX]

OP, You cannot create Quad-Channel with any Zen based CPU that does not have a second die active. Its physically impossible.

He was on about x299, but I've misread x299 as x399 a couple times already myself.

 

[batboy]

We'll never speak of this again.

 

[Dolk]

Ahhhahah, One of those days

 

[Woomack]

I don't want to create new thread so I will leave it here:
http://www.asrock.com/mb/Intel/X299E-ITXac/index.asp#Memory
Quad channel sodimm on X299 ITX board ... all is great but QVL list includes only standard DIMM while mobo has only SODIMM slots ... and how can users trust these lists ? The same is doing almost every other motherboard manufacturer claiming that some of the memory kits are working while it's impossible or nearly impossible. But really standard DIMM tested on SODIMM mobo ?

 

[EarthDog]

Probably just going by whats under the hood... worked with 6 six kits, has to work with all 48!

 

[SPL Tech]

Uh no, that won't work. The Integrated Memory Controller is on the CPU itself. Chipsets are now largely relegated to what we old timers would have called a Southbridge back in the day.

Northbridge. Southbridge controls I/O functions like USB, PCIE, etc. Northbridge has the memory controller and functioned as the Intel chipset.