will the future be northbridgeless?

[Uranium-235]

with intels new lga 2011 design integrating 40 pci-e channels into the processor itself (minus 4 uplinked to the northbridge that contains a 8 pci-e hub). and amd fusion and some intel cpus integrating graphics into the cpu, allowing onboard power to shine due to low memory latency and few heating restrictions (northbridges can't have powerful gpu cause of the usually passive heatsinks)

how long before we see cpu integrated sata, usb, firewire? what then? what else is left?

I have a feeling this might happen, but it will probably have 2-4 dedicated pci-e channels for the audio/nic chips, not putting them into the cpu, which would probably put realtek out of business

[mariushm]

Re: will the future be northbridgeless?

AMD has 32 lanes in their cpus for a long time...

Anyway, not gonna happen soon....

Integrating everything requires investing billions in new manufacturing plants that can shove more transistors into a small die, which means only the big players (intel, tsmc, the old amd factory they sold) may be able to invest in.

The manufacturing capacity of the three will be limited, and since there would be only amd and intel capable of it, the prices will go high.

This allows smaller players like ARM and Via to keep their market share - some people will always want a simple machine. Also, there will always be a market for add on controllers, people are paying now for motherboards with 10 sata ports, with 14 usb ports and so on

Also, it's much faster and easier and cheaper to do respins of a northbridge in case you have bugs in a sata controller or a usb 3 controller - these are kind of modular within the northbridge.

It would be a pain to fix stuff inside the cpu and would cost a ton more to re-do all the stuff that's used in the process of making a processor.
PCI Express and Memory controller were integrated because the memory bandwidth is very important for both. USB, Sata and other protocols don't have that much memory bandwidth.

Ah, and don't forget these northbridge chips are often made on older processes, so when a company builds a whole new production line for processors because they can't upgrade the old one, they still want to keep their old line running and pay its investment. Sometimes it's more expensive to re-arrange the chip internals for the new lower um process than to keep making it on the old process.

[Uranium-235]

Re: will the future be northbridgeless?

actually they might not even need to put it in one die. maybe they can split multiple dies up and attach them all in one package

I can find no evidence that AMD does have integrated PCI-E. I know am3 does not, and what little I found about FM1/FUSION/APU tells me the same

[mariushm]

Re: will the future be northbridgeless?

You're right, I apologize. AMD still has the PCI Express separately in the northbridge.

For some reason when I wrote the previous post, in my mind I was thinking all the time about the southbridge.... I don't know, the only excuse I'd have is being tired.

Here's for example one of the latest AMD combos (from Anandtech 990FX motherboards test):



Yeah, it would make sense to move the pci express lanes inside the processor. I'm thinking now it would make sense to leave it separately if they decide to move the USB 3.0 ports within the northbridge.

According to the article "890FX and 990FX HyperTransport 3.0 should enjoy transfer rates of up to 5.2 GT/s, unless you use an appropriate processor when HyperTransport 3.1 kicks in to give a 6.4 GT/s transfer rate."

So there's 6.4 GT/s between the CPU and pci express slots, which is kind of enough right now.
If they move the lanes inside the CPU the pin count will grow a lot, they'll need to change sockets, the cpus won't be backwards compatible...

If they leave it like it is now, they could potentially add usb 3.0 and maybe thunderbolt and have them share the hypertransport link

[Uranium-235]

Re: will the future be northbridgeless?

I'm not talking about this or even the next generation. Probably 2 or so generations from now, when they will have a new package/socket

yes 6.4GT/s but what about latency? can you imagine if they built in on-die SLI or crossfire? can you imagine how much data could be passed between cards right off the chip die?

as far as USB goes, by two generations, 3.0 will be the mainstay and integrating 6-12 (depending on if its a budget chip or enthusiast chip) ports should be easy. and again, adding 4-8 dedicated PCI-E lanes for separate (audio, nic, sata, raid, usb) controllers would be smart. but I predict the most that will happen for a long time is a pci-e hub, taking those dedicated lanes and hubbing them to added slots