Originally posted by bridgman
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SiFive Is Launching The Most Compelling RISC-V Development Board Yet
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Originally posted by brucehoult View PostThe 2 1/2 year old 1.5 GHz HiFive Unleashed is already faster than a Pi 3.
If this has come in at 2 GHz as anticipated (they don't seem to have said) then it should be similar performance to an Odroid C4 (quad 2.0 GHz A55) or Pi 4 (lower MHz but higher IPC).
The new version is 2-way in-order so should get close to A53 on integer, but behind on floating point and SIMD. There is no chance it will get near the performance of a Pi 4 since that uses the 3-way out of order Cortex-A72 which is significantly faster.
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Originally posted by _ONH_ View PostCouldn’t amd license them an old GCN gpu ip for cheap, limited cu.
why don’t you release new sub 75w gpu?
That market is already at the point where supply chain challenges are dominating, so I doubt that anyone would want to license an existing design and take on that pain when it's easier to just buy the chips in volume for a good price.
I do miss the good old days when humans set prices instead of computers and older stock gradually had its price reduced to move it out rather than having scarcity-based algorithms charging $700 for what used to be a sub-$100 card in the hope that someone would buy it.Last edited by bridgman; 30 October 2020, 11:30 AM.Test signature
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Originally posted by rastersoft View PostIs there an "arduino-like" board with a Risc-V microcontroller?
Try a "RISC-V" search on aliexpress or the like.
The GD32V is particularly interesting. It's a RISC-V CPU core with STM32-like peripherals.
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Originally posted by bridgman View Post
Unfortunately because of iGPU progress the market for small low power dGPUs is in that awkward "really small but not zero" spot and looks to stay there for quite a while, so it's hard to justify a lot of ongoing investment. We already make Polaris-based cards (RX 540 and RX 550 aka Lexa) that run without a power connector near laptop power levels.
That market is already at the point where supply chain challenges are dominating, so I doubt that anyone would want to license an existing design and take on that pain when it's easier to just buy the chips in volume for a good price.
I do miss the good old days when humans set prices instead of computers and older stock gradually had its price reduced to move it out rather than having scarcity-based algorithms charging $700 for what used to be a sub-$100 card in the hope that someone would buy it.
Thank you very much for explaining. I alsoiss thoser ended xard's, but as you say, the 540/550 will probably have to bridge the gap for the time being.
Hi
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Not only would I call this a "developer board", but I would call it a "low-level developer board." I think every build maintainer in the Debian project should be furnished with one of these, somehow or other (even if it's SiFive themselves paying for it, out of pocket, calculating that this expenditure will be a huge help to boosting their own ecosystem). Not to mention anyone in the linux world, who has lower-level, Video-related expertise, maybe mainlining some kernel drivers for commodity, easily-available PCIe video cards, etc.
IMHO, this board is especially suited for getting a bunch of new bugs discovered, and fixed, having to do with various low-level toolchains being used in Debian package building, as well as lower-level libraries, and getting anything related to video working: X.org or Wayland support, and maybe even Vulkan.
https://wiki.debian.org/RISC-V#Toolc...reaming_status
My prediction is that the next board SiFive makes down the road, having more power and cheaper cost (as in, decent desktop-grade performance on par at least with a Raspberry Pi 4), will more realistically get into the hands of a much larger number of Debian Developers who debug/maintain packages that are much higher level (GUI apps, and desktop environments), as opposed to the lower-level toolchains/libraries, and Video-related infrastructure.Last edited by esbeeb; 31 October 2020, 09:58 AM.
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Originally posted by PerformanceExpert View Post
That's not remotely possible, the Unleashed is a simple 1-issue core while Cortex-A53 is 2-way - this shows the Unleased is about halfway between a Pi 2 and Pi 3 in performance.
The new version is 2-way in-order so should get close to A53 on integer, but behind on floating point and SIMD. There is no chance it will get near the performance of a Pi 4 since that uses the 3-way out of order Cortex-A72 which is significantly faster.
Your link shows five benchmarks. The Unleashed performs about like the Pi 2 on the two encryption tests. Unsurprising as it doesn't have specialized instructions for that as it's a minor part of most people's workloads. On two other benchmarks the Unleashed is the outright winner, and on the 5th it is close to the Pi 3.
I think this demonstrates that my claim is close enough to reality.
You don't seem to be aware that a dual-issue CPU doesn't execute two instructions in the same clock cycle anywhere near to 100% of the time. The A53 (and A7) are fairly crude in this, and probably don't even achieve 40%. The Unleashed also has much more and much faster RAM than the Pi 3.
The A55 and the U74 have much better dual issue implementations with some minor out-of-order features -- technically: they have both an "early ALU" pipe stage and a "late ALU" pipe stage, which allows them to dispatch two dependent instructions in the same clock cycle in many cases. Yes, the A72 is 3-way but again this is peak and it doesn't achieve that all the time -- the average is probably around 2, at best.
There are plenty of benchmarks showing 2.0 GHz A55 (e.g. Odroid C4) performing very close to 1.5 GHz A72.
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Originally posted by brucehoult View PostYour link shows five benchmarks. The Unleashed performs about like the Pi 2 on the two encryption tests. Unsurprising as it doesn't have specialized instructions for that as it's a minor part of most people's workloads. On two other benchmarks the Unleashed is the outright winner, and on the 5th it is close to the Pi 3.
You don't seem to be aware that a dual-issue CPU doesn't execute two instructions in the same clock cycle anywhere near to 100% of the time. The A53 (and A7) are fairly crude in this, and probably don't even achieve 40%. The Unleashed also has much more and much faster RAM than the Pi 3.
The A55 and the U74 have much better dual issue implementations with some minor out-of-order features -- technically: they have both an "early ALU" pipe stage and a "late ALU" pipe stage, which allows them to dispatch two dependent instructions in the same clock cycle in many cases. Yes, the A72 is 3-way but again this is peak and it doesn't achieve that all the time -- the average is probably around 2, at best.
There are plenty of benchmarks showing 2.0 GHz A55 (e.g. Odroid C4) performing very close to 1.5 GHz A72.
I'd be surprised if the Unmatched can beat a Pi 3, but Pi 4 is simply out of its league. Maybe the U84 will do better but there hasn't been any news for 12 months. It seems to me RISC-V people are better at generating hype than creating actual designs that run fast...
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