Hacker News Reader

Hacker News

Comment by logicallee | Hacker News Reader

Full thread

logicallee

This is very impressive. Here are the specs that they linked:

https://pine64.com/product/128mb-ox64-sbc-available-on-decem...

It has 64 MB of internal psram and these cores:

- 64-bit 480MHz RV64 C906

- 32-bit 320MHz RV32 E907

- 32-bit 150MHz RV32 E902

This is like desktop computers from 30-40 years ago I guess. There were quite a few types of applications those could run.

I'd guess that this board is inexpensive as a cheap entry-level board into the pine64 ecosystem, other boards by pine64 are more expensive. ($60-$80 range.)

View on HN

> This is like desktop computers from 30-40 years ago I guess.

30 years ago was 1990; a typical desktop computer of that era would have a single CPU at 20ish MHz, and between 512 kB and 2 MB of RAM. The Ox64 easily outclasses anything that was available at the time.

>30 years ago was 1990

Your overall point is valid, though I think you'll find that this particular calculation isn't correct. (The current year ends in a 6 so 30 years ago also ends in a 6.)

However, I just did a quick search for the Doom release date, which was 1993 and the original system requirements which is Memory (RAM): 4 MB and Processor (CPU): Intel 486DX (66 MHz).[1] So in terms of RAM this is 16x as much and in terms of MHz it's 6x faster on one of the cores. So it's definitely desktop-class for 1993. (33 years ago). As you state, it's much faster than desktop class in 1990.

[1] I only just looked at Google's AI summary, maybe it's wrong: https://imgur.com/a/LbhAmGp

Whoops! Either way - 480 MHz and 64 MB of RAM would put this more on par with a 2001 iMac (400-600 MHz, 64 MB RAM on the base model). And that's not even counting the other CPU cores or the (probably much better) IPC of a modern CPU design.

The MHz ratio really understates the difference.

66MHz probably wasn't an 80486DX; as far as I can recall, those only went up to 50MHz. It would have to be a 486DX2, with the RAM running at only 33MHz. https://netlib.org/performance/html/dhrystone.data.col0.html says that a 486DX2/66 was about 31 to 51 Dhrystone MIPS.

https://www.riscvschool.com/2023/03/09/t-head-xuantie-c906-r... says the T-Head (Honey Badger) C906 RV64 core is about 2.3 Dhrystone MIPS ("DMIPS") per MHz, so we should expect the 480MHz C906 to be about 1100 DMIPS.

So the clock speed is only ≈8× higher, but the actual speed gap is probably closer to 32×.

And, for vectorizable workloads, we should expect the V extension to give us another 4–8× boost, so 128×–256× the DX2/66, which didn't even have MMX.

Reply on news.ycombinator.com