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Comment by qwerty456127 | Hacker News Reader

IMHO PCIe (and SDRAM) should be the only interface exposed by a modern CPU. On-board graphics, audio and NICs usually are shitty anyway. SATA is not relevant any more - we better plug an NVMe SSD into PCIe (or get a controller if actually needed). Full USB-C (or ongoing USB-4) means Thunderbolt which is PCIe. Why waste silicon on anything but PCIe then?

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> On-board graphics, audio and NICs usually are shitty anyway.

Onboard graphics, audio and NICs are perfectly functional and more than enough for most people. Both in work environments and at homes. They've not been in a shitty category for years now. They won't break any records, but they will display websites at high resolution, play clear music, and provide more bandwidth than the link to the internet can handle.

Just look at the number of Lenovo's AIOs (and similar solitons) in offices.

> Full USB-C (or ongoing USB-4) means Thunderbolt which is PCIe.

USB 2 is a fraction of the price. (And power and board space)

I really love the pushback here. Yes how awesome it is you are privileged enough to always be able to acquire the best of the best and look down on other "inferior" devices.

But 99% of the rest of us just need things that work and allow us access to good performance.

I actually use everything built-in because what I use are a decade-old business laptop, an office desktop and a RaspberryPi. But going to buy a good desktop (as I used to have 2 decades ago) I would rather buy a good mainboard with as many PCIe slots as possible (and no built-in devices if this were possible), the cheapest discrete cards for everything and upgrade them as I see fit. I doubt the cheapest/used discrete card for anything is going to be worse or more expensive than a built-in non-removable version.

> play clear music

Then why are there so many audio hats, let alone USB audio dongles used even in the RaspberryPi world?

I believe the GP's post was more general in proposing PCIe attachment. Though you are correct is asserting that stock Pi audio is junk.

That feels really counter to what I see. Maybe five years ago I'd have agreed with you, but now-a-days on-board graphics, audio and NICs are way better than they used to be.

Don't get me wrong, I still run a discrete GPU for gaming, but for a lot of people onboard GPUs provide a good experience, and often much better power efficiency.

Power and convenience. Power usage by PCIe is a factor for mobile devices. And convenience, in that "shitty" onboard graphics, audio, and NICs are good enough for 90% of the use cases for most devices.

> Why waste silicon on anything but PCIe then?

Power. PCIe is a fairly power hungry link. On-die parallel connections are incomparably more efficient.

Special low power links like MIPI PHYs also have their place.

USB is high enough speed that you will get quite a bit of overhead from USB>PCI>memory route, and back.

Audio is a particular pita, network too needs as close, and direct as possible connection to the CPU to get maximum performance.

In many cases, these all can use the same pins anyway. Like on some NXP SoCs I've worked with, you just had a bunch of SerDes lanes that could be assigned to any number of functionalities (SATA, SGMII, PCIe, etc.).

Massively depends on the use case. Why waste board space, assembly complexity and power on PCIe when a SoC does just fine?

Other than the integrated graphics that are directly part of modern Intel CPUs, everything else you mention is typically internally connected by PCI-e. Onboard USB ports lead to a controller which talks to the CPU via PCI-e, for example.

PCI-e lanes are a limited resource on a CPU and really fast. Dedicating one to a keyboard, for example, is probably inefficient.

I have heard (don't know too much about it) some Intel NICs are able to place network packets right in the CPUs cache for maximum speed, this probably can't be done via PCI-e.

This comment reeks of privilege

GPU yes, rest no.

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