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You yourself repeat a very common misconception and false analogy. Intel and AMD start new microarchitecture design work every 2-3 years because (Intel, at lea

You yourself repeat a very common misconception and false analogy. Intel and AMD start new microarchitecture design work every 2-3 years because (Intel, at least) base their sales on offering the latest and greatest. They seek peak performance, which is exactly what gamers/scientists/prosumers want. But for large swaths of the market, you don't need that. Think of your average consumer/small business owner. By and large, most of them are using 3-5 year old PCs, and even then the processors within those 3-5 year old PCs were probably last-gen when they were purchased. Or think military -- the ability to have a home-grown, openly-vetted processor that you can tape out with a trusted domestic supplier would eliminate a number of security concerns. Don't let great be the enemy of good here. If you can build a decent RISC-V core that can compete with an Intel Core 2 Duo, you've got all the horsepower you need for the average consumer.

freeone3000 8y ago
Core 2 Duo? You're aiming way too high here. A RISC-V core that can compete with a Cortex A9 or a Snapdragon 820 would be exceptional.
- tonysdg 8y ago
  Maybe a Pentium IV then? I don't think RISC-V -- or any processor really -- gets taken seriously in the desktop/laptop space unless it can compete with one of Intel's earlier chips.
  - jononor 8y ago
    Unlikely that anyone will even try to target desktop/laptop market with a RISC-V CPU, it is a very established market without much future growth. The plays will be in embedded devices, especially areas which requires pheripherals with tight integration with the CPU, this is where an open and extensible ISA can be a significant benefit. Examples today are controllers inside SSDs/SDcards. In future maybe also microcontrollers with integrated machine/deep learning co-processors.
- lkcl 8y ago
  nonsense. rocket-chip has been taped out at 45nm and achieved 1.5ghz, years ago. india's shakti core is going into 20nm and as a 6-stage pipeline will run at 2.5ghz. as that one uses only 120mW, even 16 2.5ghz cores would only consume around 3 watts (!!!). caveat of course: the L1/L2 cache power consumption isn't included in that figure, but, crucially, with the Compressed Instructions reducing cache misses by 20-25% that's equivalent to having approximately double the I-cache size. basically by a fresh start they're on to a winner.
Nokinside 8y ago
I did not deny that there will be completely free designs for small volume applications and specific niches. They will be very low performance and not going to be competitive in mass markets in low price or high price. > Think of your average consumer/small business owner. Optimizing processor for low-cost price is also very demanding.

freeone3000 8y ago

Core 2 Duo? You're aiming way too high here. A RISC-V core that can compete with a Cortex A9 or a Snapdragon 820 would be exceptional.

tonysdg 8y ago
Maybe a Pentium IV then? I don't think RISC-V -- or any processor really -- gets taken seriously in the desktop/laptop space unless it can compete with one of Intel's earlier chips.
- jononor 8y ago
  Unlikely that anyone will even try to target desktop/laptop market with a RISC-V CPU, it is a very established market without much future growth. The plays will be in embedded devices, especially areas which requires pheripherals with tight integration with the CPU, this is where an open and extensible ISA can be a significant benefit. Examples today are controllers inside SSDs/SDcards. In future maybe also microcontrollers with integrated machine/deep learning co-processors.
lkcl 8y ago
nonsense. rocket-chip has been taped out at 45nm and achieved 1.5ghz, years ago. india's shakti core is going into 20nm and as a 6-stage pipeline will run at 2.5ghz. as that one uses only 120mW, even 16 2.5ghz cores would only consume around 3 watts (!!!). caveat of course: the L1/L2 cache power consumption isn't included in that figure, but, crucially, with the Compressed Instructions reducing cache misses by 20-25% that's equivalent to having approximately double the I-cache size. basically by a fresh start they're on to a winner.

Nokinside 8y ago

I did not deny that there will be completely free designs for small volume applications and specific niches. They will be very low performance and not going to be competitive in mass markets in low price or high price. > Think of your average consumer/small business owner. Optimizing processor for low-cost price is also very demanding.