Taking Suggestions for Secondary Compute Card (PCIe)

Hardware
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No suggestion is stupid, the only stupidity is negative criticism. We’re doing it because we want to. We’ll get a talos later. No we don’t want to buy a xeon machine, and no we don’t want new hardware.

Now that I have those comments halted immediately.

So me and @THEkitchenSINK are building something stupid. The sink bought a G5 quad 11,2, the good one with the good cooler and controllers, for 40 bucks. In the time since we have been plotting what exactly to do with it since we both have a high interest in the platform, and specifically this model of machine.

Today I had something of a schizophrenic idea only a mad scientist could have.

What if we put a phi in it?

And then rabbit holes ensued. However, phi’s are expensive. Even the 6GB models. So here I am thinking about other options. Theres plenty of arm dev boards, possibly X86 ones, all sorts, but I honestly don’t know what to look for. So, I open this thread looking for every possible idea.

Every. Single. One.

If theres a PCIe ARM board you know about, tell us. If theres an atom server socket on a pcie reiser, tell us. We want to know every option.

The intent here is to have stupid compute performance, with even the potential to host X86 VM’s and pass through an RX550 or something to run something like quake or the like. I’m personally looking at this as a science experiment, one of which I’m not sure has been done.

We are working with this machine.

https://everymac.com/systems/apple/powermac_g5/specs/powermac_g5_quad_2.5.html

We are also looking at overclocking GPU’s, pulling the flatbed PSU out and plopping a pi in for sleep timing based on when compute is needed (SSH to pi, pi wakes machine up from sleep / hibernate [in the event the machine needs to be moved], pi sleeps machine when user logs out), replacing the PSU with something like a 2000W titanium / platinum PSU, adding NVME (which sink has already done as far as I am currently aware, or at least its been ordered), adding SAS 12GB, and many many many other things.

But for now, suggest compute cards. We need to know.

Alternatively, if you know where to get a PHI 5110P or better for less than 250, let us know. We’re not sure where to look other than ebay.

Thanks guys.

3 Likes
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This is where I got my Phi.
Seller is very flexible on offers (100$ starting, but you can offer ~80$)

However I really don’t recommend a Xeon phi for a Powermac G5 or anything with nonstandard non intel spec UEFI.

The Xeon Phi requires 64bit PCI-e addressing support (aka Above 4G decoding) Since it maps the ENTIRETY of it’s 8G/16GB of RAM into a PCI window.

Dr Donald Kinghorn Is a bit of a Xeon Phi expert in a way


IMG_20190819_180453.jpg3806×2441 834 KB

Just look at that Region 0 Memory space (8G!!)

To use Xeon Phi you also need to run a full UEFI stack.
No CSM of any sort.

And to my best knowledge most of this is well and truly not supported on PowerMac. Just newer Xeon / AMD boxes with MMIO 4G decode ( >40bit / 1TB PCI-e address space)

The MPSS software stack (something I’m currently battling) is also pretty nuts

http://registrationcenter-download.intel.com/akdlm/irc_nas/11733/README.txt

https://software.intel.com/en-us/articles/intel-manycore-platform-software-stack-mpss

http://industrialinformatics.fel.cvut.cz/xeon-phi-installation-gentoo-linux

The cards themselves (At least the early 64bit P54C + 512 SIMD based) Knights Corner X100 (71xx/ 51xx/31xx) based cards appears to be around 2 TFlops single precisions / 1 TFlops Double precision compute for heavily vectorized (512bit AVX-like SIMD)

Also fun fact the card basically loads it’s OS from an NFS share over a local only IP network across the PCI-e bus.

http://ephelis14.rssing.com/chan-8140715/all_p16.html

And you can SSH into it. :smiley:

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Wery inheresting, I’ll have tomread through that later if sink isn’t already. Atb studyitg for a state license test.

The powermac has no efi at all. It operates on openfirmware and thus allows complete access to the hardware onboard. What do you suggest otherwise? We were hoping for something absolutely stupid, and a phi was as stupid as we could come up with. Even if stupid, functionality is wanted as well.

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Still need ideas folks :3

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GPU computing, M and K series Teslas can be found for cheap.

Not technically compute, but you can sometimes find PCIe FPGAs for relatively cheap.

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No PPC compatible drivers.

And I am not spending 2 years porting them XD

2 Likes
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From that Top 5 Xeon Phi Misconceptions:

I’ve had more than one person ask me if they could run Windows programs on the Phi using “Wine”, sorry, that’s not going to work!

That sounds like exactly the kind of madness I would suggest; imagine porting the UEFI bits of the Phi initialisation blob, then getting Wine running on the Phi cores!

Everymac lists have the max RAM capacity of the last G5s at 16 GiB, so maybe it would be possible…

Regarding the UEFI vs IEEE 1275 (Open Firmware) problem, if the UEFI normally runs an x86 blob for card initialisation, can one theoretically keep the card non-initialised during boot and then use QEMU to run the blob?

There are POWER8 and POWER9 drivers for Tesla P100 and V100 respectively. I wonder, if you compare the x86 drivers for M/K with the x86 drivers for P/V100, could that be a starting point for what needs to be changed to modify the POWER8/9 driver to work with M/K Teslas?

On a more serious note, I have heard of some x86 IBM servers having a secondary PowerPC card of some sort, that could be amusing.

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Yes and ATM theres access to a 1 power 4 system XD later on there’ll be power 9 LG to play with, just not right now.