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Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

jeffgeerling.com

41–50 of 74 posts

Re: Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

#41
post #8

Once you get to this size and price, there’s no point in using a Pi…there are much more powerful options available.

I guess it makes sense as a development board: if you are building a product around a Pi Compute Module you can use this board for quick prototyping before building your own product-specific board. But any hobbyist looking at this should seriously consider the various Pi alternatives around the $200 mark first. Or just buy a used PC.

For the sub-$100 price point, you often can't beat discarded thin clients. There's a steady of stream of units always hitting eBay, including ARM ones like the HP T-series and x86 ones like Dell Wyse units.

If you really just need something that comes with a case and power supply, might already have wifi, and has a few USB2 ports to plug things into, these are great options.

Re: Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

#42
post #30

Some friends and co-workers of mine have an ongoing bet/joke... Who can find something that the Raspberry Pi can NOT do. One more thing scratched off the list!!

Boot without a GPU - Pi can’t do that :)

Good one. Putting it on the list.

It's an amazing little board, list is pretty short :)

Re: Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

#43

We're like one or two hardware generations away from having a VME backplane like environment where we'll be able to do some truly nifty and nasty things, at home and hobby levels. The politics of getting a standard out that isn't owned by (and therefore twisted to favor) a couple of big companies is challenging, but it's happened before, right? (crickets)

I'm pretty sure PCIe is that today.

PCIe CPUs may have failed commercially, but they prove that its possible (Xeon Phi).

PCIe GPUs are common. 4x or 8x GPUs are your typical mining rigs.

Perhaps most common is PCIe SSDs (aka: NVMe or M.2 slots).

------

So our modern PCIe "backplane" gives us storage, extra compute (GPUs most commonly), longer-distance network access (fiber optics, ethernet, etc. etc.). What else do you want?

Sound cards (especially MIDI instruments support) maybe? Dedicated video processors? A big problem with dedicated devices is that modern CPUs are so powerful... there's not much point to buying an ElGato H264 encoder anymore when you can just buy a 16-core CPU instead and do it all in software.

----

Your standard Threadripper motherboard has 4x16 PCIe slots, and I'm pretty sure 8x PCIe to each of the slots, with full support of bifurcation (splitting into smaller PCIe slots). Surely that's enough for any of your hobby projects?

Re: Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

#44
Recent 4-cores, 2.0+ Ghz and 4GB RAM ARM SBC's are plenty powerful for most tasks a home user may need. Media consumption, browsing, light text editing, editing the weekend video and even compiling small code bases. People have been doing that in chromebooks for years.

Unless you need to compile large code bases, edit serious videos, process huge amounts of data or CAD/games, a simple cheap ARM computer should be enough.

Too bad the desktop was taken by a monopoly and monoculture of x86-64 with windows where you are locked if you need compatibility with some proprietary formats or tools/software.

Re: Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

#46

Recent 4-cores, 2.0+ Ghz and 4GB RAM ARM SBC's are plenty powerful for most tasks a home user may need. Media consumption, browsing, light text editing, editing the weekend video and even compiling small code bases. People have been doing that in chromebooks for years. Unless you need to compile large code bases, edit serious videos, process huge amounts of data or CAD/games, a simple cheap ARM computer should be eno…

I wonder if there is a blog post in this somewhere, that I could write.

I have a bunch of Pi 4s (4GB). I just put one in an Argon M.2 case and was wondering what to do with it.

I have a "gut feel" for how my workstation should behave, I am a (backend) software engineer by profession, tend to work my day job on an i7 laptop (XPS 15, Ubuntu) but at home I'm on Ryzen 7 1800X (Manjaro) and Ryzen 9 3900X (Debian).

Is there some useful non-benchmark type "measurements" I could take by using a Pi as a workstation for a few days, that people would be interested to read about?

Re: Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

#47

We're like one or two hardware generations away from having a VME backplane like environment where we'll be able to do some truly nifty and nasty things, at home and hobby levels. The politics of getting a standard out that isn't owned by (and therefore twisted to favor) a couple of big companies is challenging, but it's happened before, right? (crickets)

I'm pretty sure PCIe is that today. PCIe CPUs may have failed commercially, but they prove that its possible (Xeon Phi). PCIe GPUs are common. 4x or 8x GPUs are your typical mining rigs. Perhaps most common is PCIe SSDs (aka: NVMe or M.2 slots). ------ So our modern PCIe "backplane" gives us storage, extra compute (GPUs most commonly), longer-distance network access (fiber optics, ethernet, etc. etc.). What else do y…

What got me off about VME when i looked at it was the immense amount of small market, single purpose hardware that had been thrown on it and was "technically" compatible. It enabled some stuff like timed traffic lights in a way similar to how Arduinos have opened up hobby level "printer-oid" mechanisms.

For reasons i cant articulate well I'm itching for a bus where CPU and GPU and RAM and IO all live together in hippie harmony. The hardware's all there and dancing to some little basic machine controller CPU anyway so lets open all that up and make everything a first class citizen, hopefully on some interconnect that will last a few years and gather some interesting surplus hardware to filter out to hackers.

As to modern hardware, if i had all my dreams coming true, I'd be grabbing one of the "mining" motherboards with all that I/O broken out into channels and putting SDR's on them to make pretty waterfalls of the biggest bites of the radio spectrum i could visualize.

Re: Mini-ITX Seaberry Adds 11 PCIe Slots to a Raspberry Pi

#48

Earlier quoted context omitted.

That's probably the way to think about it. PCIe devices communicate point-to-point over dual-simplex serial connections. If you have something like a Raspberry Pi CM4, which only has a single PCIe lane, then there's going to be a PCIe switch.

Interesting, thank you!

The other neat thing is that peer-to-peer PCIe transactions do not have to go through the root complex (the Pi in this case).

Say you have a GPU and an NVMe drive or video capture card plugged into a PCIe switch, which is then plugged into the Pi. If your software supports having these devices directly communicate, they can do so as fast as their PCIe links support doing, even though there’s only the tiny link to the Pi.

Peer-to-peer transfers are only limited by the smallest link on the path between two devices on the tree, rather than the smallest link in the tree.

A real world example is some of the big GPU compute servers. Some of the 4U chassis can house 20 or more cards. Many of them have all of the GPUs (320 or more PCIe lanes) plugged into an array of PCIe switches which may constrain them to 16 or 32 lanes from the CPU. The GPUs can all talk to each other a full speed, but only a few can go full speed to the CPU at a time.

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