xphi

Xeon Phi board bring up

Hardware

Setup

Intel® Xeon Phi™ Coprocessor 5120D Intel Xeon Phi Datasheet
Z97 mini-ITX Motherborad ???
PCIe x16 to x24 converter (todo)

Thermal solution

Board has 4 x M4 mount holes with 81 x 85 spacing.

All layers connected using white thermal compound.

Both sides use similar (compound + copper + compound + aluminum) passive cooling solution for GDDR 5 chips.

2015-10-10 Build session:

Bottom side memory

Assembly starts from the bottom side of PCB.

Copper shim pads 15 x 15 mm. On top of 16 GDDR5 chips. Two halfs in the top and the bottom row.

Had-cut / scrape aluminum panel fixing copper shim pads:

4 x M4 x 25 screws via nylon washers keeping all attached to the PCB.

Top side memory

Copper shim pads are very similar for the bottom story.

Similar aluminum piece. Holes are M4 threaded.

Two Aluminum plates screwed together. The rest of the screws pops up and will be used for CPU cooler attachment.

CPU

Using Antec KÜHLER H2O 650 Liquid cooling solution ($39) for the CPU.

Cooler bracket requires trimming to non-standard 81 x 85 holes.

ToDo

Apply final thermal compound to the CPU
how to monitor temperatures? control FAN speed?

PCIe x16 to x24 converter

Phi board comes with x24 edge connector, that is not compatible with ANY reasonable (available) Motherboard. The x24 connector using only 16 of PCIe lanes, and uses ther rest of pads for +12V power delivery.

PCIe x16 provides 1-82 A-B pins
A/B 83-87 are reserved

top	sig	botom	sig	from
B1-82		A1-82		from PCIe x16
B83	???	A83	NC
B84	???	A84	NC
B85	PWR/GND???	A85	GND
B86	NC	A86	NC
B87	NC	A87	NC
B88-115	+12V	A88-115	GND

Our plan:

Option 1

PCIe x16 extention cable $7
Remove PCIe x16 connector from the extender
Solder PCIe x24 230 positions connector (STRADDLE MOUNT) ~$12
Solder Power cable

Option 2 👍

PCIe x16 extention cable $7 (I received 2 extenders)
Trim x16 connector on the extender
Trim one more PCIe connector
Glue second connector to the extender
Solder Power cable

Option 3

PCIe Riser Card x16 $15
Rework PCIe connector to PCIe x24

Common

Both options require power cable modular PSU 2 x 8-pin (+12v) GPU connectors (2 x 150W)?

2015-10-12 Build session:

Received two PCIe x16 extention cable $7

Testing with GPU card showed electrical problems.

Found several wires in the air!

Started resoldering cable.

2015-10-17 Build session:

After faling several attempts to resolder the extention cable, we have decided to unsolder wires, and use only hal of it. The problem, is that 2-side PCB was so cheap that several copper pads came-off the board. That made the board more or less useless.

For the next attempt we ordered JET-5304 PCI Express X16 Extender. ($11)

We are going to check it with GPU card, and then rework the connector x16 to x24 with extra +12V power if first step is successfull.

2015-10-24 Build session:

PCIe x16 riser board, PCIe x16 connector, hacksaw, superglue and ... we build extended x16 to x24 riser board.

Power cable (+12V) soldered directly to the connector and has 8-pin connector compatible with EVGA Supernova PSU.

2015-10-24 Smoke test

My Z97 computer failed to boot with Xeon Phi board in. Xeon Phi on-board LED blinks 8Hz. Power consumption is normal. We have to try with more advanced chipset tomorrow.