Friday, November 04, 2016

The Independent Loading Mechanism ILM

Subtitle: It's never Easy

This is a further post about Marcus' attempts to construct his next generation Computer workstation.  A battle of man against machine.  Whilst the purpose is to talk about the Independent Loading Mechanism  (ILM)  which is the modern way Computer Processors are held to a Motherboard,  I will start with some history

Processors in the 1970's

This is a screenshot from my Cromemco ZPU Zilog Z80 processor card from about 1976.  You'll see a Dual Inline Package CPU.  The technical manual is here.  The Z80 contained about 9000 transistors. Simple Packaging and no cooling required.

Processors in the 1980's
Fast forward almost 10 years.   A Motorola 68020 Processor from my Cromemco XXU processor card

Whilst the packaging is now in a Pin Grid Array (PGA) you'll notice that there is still no heatsink.   Although there are now about 200,000 transistors, total power consumption is still only about 1.75 Watts.

Jump to 2016

By comparison each Intel Xeon processors I hope to install in my 2016 workstation

-  Thermal Design Power  145 Watts
-  Socket FCLGA2011-3
-  7 200 000 000 i.e. 7.2 Billion Transistors

I know, it is just bonkers.  These Processors are based on Intel's 14nm process. Just wow.   And they need:

- A way to securely install them
- A way to cool them.   From this article you see that the Xeon is using  over 80 times the power of the Motorola 68020

The Independent Loading Mechanism provides a way for this Flip-Chip, Land Grid Array (FCLGA) processor to be securely located and easily replaced.

The ILM surrounds the CPU Socket and for Xeon 2016 chips based on usually Broadwell-E Architecture the socket is called a LGA2011-3

If you look closely you should see some key marks on the socket edges.  They are unique to LGA2011-3 processors meaning that if you try to place an older generation CPU here it won't locate.

Cooling the Xeon
In order to remove the 100W plus of heat generated we need cooling.

If you place the CPU into the ILM without any cooler and start the computer in only a few seconds your CPU will have overheated and have been frazzled. Don't do that!

The 2010-ish way to cool a processor, still used, though less so; is to mount an aluminium heatsink on top of the processor and fan cool that finned sink.

Noctua NH-L9x65

The 2016 way is usually to have a smaller heatsink connected via fluid to an external radiator.

Corsair H90 Hydro cooler

And then Disaster Strikes

So after careful planning, the Supermicro X10DRi-T motherboard was ordered with a companion Corsair Hydro H90 Cooler.

I tried to mount the cooler on top of the motherboard mounting bracket.

It did not fit

I just could not believe it, the holes don't align, and in disbelief spent a few minutes rotating it round,  trying it from all angles!

Poorly Documented to Me

Now that I know I could pretend I always knew.  But I did not, and the local Digitec website did not tell me.  Worse,  you cannot return the components back to Digitec for a full refund unless the packaging is unopened, even though IMHO their CPU Cooler Webpage told me their cooler fits LGA 2011-3 sockets.  What it really meant was: Cooler fits LGA 2011-3 sockets with Square ILM only.   Well, of course.

It was time to do more research and

- I joined the Official Corsair Forum
- Corsair knows about this issue
- But they have no plans to include a narrow ILM mount
- Turns out that this cooler is subcontracted to Asetek for manufacture, because you know, nobody does anything themselves these days, it's all outsourced or subcontracted!
- Asetek can independently sell you a Narrow ILM mount, but only from America
- So 7 days later, by expensive airmail from the USA, arrived 2, narrow ILM mounts

The Happy Ending

So now it is all working.   A 7 Billion transistor CPU,  attached to a closed loop, liquid cooler.   Some change from my first serious air cooled Zilog processor with a then 9000 transistors.

In Summary

Life today, it's so complicated .....

Avril: Complicated

An so, the Build continues. Inching forward.  Fingers crossed, no more challenges!

ILM mechanism with lever patent