I wonder if OEMs will find it easier to design a single 100W cooling system instead of 2 45W cooling systems to fit inside an ultrabook. Hoping for a new XPS15!
I'm not sure how good it is for AMD since their Ryzen G series APUs which also aim for the 45-60W target come with a much weaker GPU (11 CUs and no onboard memory).
Sure they would be cheaper but it doesn't really matter that much the OEMs price the laptops too close together now for that to make a difference.
AFAICT, Coffee Lake has 24 PCI-E lanes, 8 of which are used to connect to the chipset. If they used all remaining 16 for the GPU, then NVMe and thunderbolt connections would have to go through the south bridge, affecting latency and throughput.
Intel doesn't connect to the chipset with PCIe, it does that with DMI.
Coffee Lake only has 16 PCIE lanes on the CPU, 4 DMI Lanes (about equivalent to 4 PCIE 3.0 lanes) which connect to the PCH and 24 PCIE 3.0 lanes coming from the chipset.
I over simplified. DMI is a PCI Express variant. I thought it had increased to 8 lanes in Coffee Lake, but I was mistaken. That makes it even more important to save some of the CPU PCIe lanes for NVMe and thunderbolt.
I guess I would have preferred to see it be a client on QPI and be cache coherent with the rest of the system, rather than using PCI at all, but yeah, that's asking a bit much on this super short timeframe.
I guess I'd like to see much tighter integration between the two chips so that we don't have to write code that avoids the PCI bus at all costs. Today you fit your entire working set into VRAM and don't touch it from the CPU, so it's sort of hard to say "it's not a deal we don't saturate the bus anyway" when that's only because we bend over backwards to not touch the bus in the first place.
I would imagine that they took the best GPU chip they could afford the space and power for, and found that 8 channels was enough for 99% of their customers?
I assume adding more channels takes space, perhaps the GPU would have had to be lower performance to add more channels?
I wasn't thinking about technical constraints, but economic ones. The market that would be able to benefit from this kind of optimization would be very limited as a % of PC gamers (which is already a limited market compared to consoles AFAIK).
It looks like Intel won't be selling a socketed version of this, which means this will be available only in laptops and NUCs. I've had trouble with Linux on NUCs in the past. So, I really hope this goes into a new mac mini.
