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AMD Ryzen "Raven Ridge" Comes with a Limited PCIe Interface

And for the record;

THAT is why your Ryzen 3 is under-performing. Get another stick of ram for that bad-boy and watch it shine!

That goes at least double if you buy an APU like the 2400G. The chip is using main memory for graphics so memory bandwidth is key. ALWAYS use dual channel and spend the little bit of extra money for DDR4-3200 RAM with an APU. (Note that this means you'll need a B350 or B450 motherboard rather than an A320 because that's technically a memory overclock.) And experiment with the amount of RAM set aside for graphics. Some benchmarks have shown it doesn't matter but I have tried some programs where it DOES matter, a lot.
 
Interesting nobody is crucifying AMD for limiting PCI-E lanes... everybody wants at least 2 million of them from Intel.

So, you can install a graphics card (at x8, but that's fine) and a NVMe drive... and 4 lanes "dedicated as the chipset-bus". Not sure what that last part means... but I'm guessing it means it's taking 4 lanes and using that for internal system communications. Are there any lanes available by chipset to install anything else?
 
So, you can install a graphics card (at x8, but that's fine) and a NVMe drive... and 4 lanes "dedicated as the chipset-bus". Not sure what that last part means... but I'm guessing it means it's taking 4 lanes and using that for internal system communications. Are there any lanes available by chipset to install anything else?

it has exactly the same pci-e lane count as Intel LGA115x.

16 in total.
4 to USB internal.
4 to PCI-E NVME
8 To gpu.

Chipset can connect other devices like intel platforms.
 
Ah, as long as there's some lanes provided by chipset for a few other things people may want/need, then I'm fine with that...
 
it has exactly the same pci-e lane count as Intel LGA115x.

16 in total.
4 to USB internal.
4 to PCI-E NVME
8 To gpu.

Chipset can connect other devices like intel platforms.
Ah, as long as there's some lanes provided by chipset for a few other things people may want/need, then I'm fine with that...
That's not quite right. Intel has had 20 lanes total at least since Skylake, with 4 of those being reserved for the DMI link to the chipset. USB is almost universally run off the chipset in Intel systems (see this block diagram, for example). RR is more limited than this, in other words, but also has some minor advantages such as SATA and USB integrated into the CPU directly.

The reason there hasn't been any uproar around this is quite simple: AMD has never marketed RR as a dGPU gaming platform, nor are they priced or positioned in the market to do this. AMD also has similarly-priced CPU-only alternatives that provide full PCIe connectivity. In other words, AMD is (reasonably clearly) communicating to consumers that RR is for non-dGPU builds, with regular Ryzen being for everyone else. You can add a dGPU, and at 8 lanes of connectivity it will perform within ~98% of a 16-lane connection, but this isn't something AMD focuses on. The selling point here is the best available iGPU. Neither is AMD marketing RR as a high-end platform - the top-end SKU has an MSRP of $169, after all.

Still, AMD either needs to add another 4-8 lanes to their next platform (unlikely to help, as it's still 2+ years out) or incorporate PCIe 3.0 switching in their chipsets. Here, Intel has a huge advantage (even if the x4 DMI link is a potential bottleneck with NVMe and 10GbE). X470 provides 8 PCIe 2.0 lanes, while Z370 provides something like 30 HSIO lanes (the majority of which can be configured as PCIe 3.0, although not above x4 at once, and with a whole bunch of other limitations when it comes to adding networking and other controllers). This is why Intel motherboards can incorporate more m.2 slots than AMD boards, and this is a noticeable advantage for Intel going forward (even if NVMe is still expensive and not really mass-market, this is changing rapidly). This is also, of course, entirely unrelated to RR's PCIe complement, as Zen CPUs have the exact same limitation.
 
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