CPU frequency 2.0GHz - real or lie


#1

On the official website Khadas.com specified Vim’s CPU frequency is 2.0 GHz against the 1.2 GHz on Raspberry.

I was buying the Vim, because it has higher frequency of the CPU. But it is lie, Vim has 1.2 GHz.
Why is real Vim’s frequency of 1.2 GHz only?

Vim has range: 600-1800 on source:

define CONFIG_CPU_CLK 1200 //MHz. Range: 600-1800, should be multiple of 24

does not 2000 again…

How to use full (2.0 GHz) CPU frequency?



#2

Actually, S905X just run 1.5GHz rather than 2.0GHz that we got from official Amlogic S905X datasheet:

There are many vendors got confused by the datasheet, refer the article from CNX-Software for more information.

Anyway, I think we need correct this.


#3

How to use 1.5GHz?
Need I modify “define CONFIG_CPU_CLK 1500 //MHz” only and rebuild uboot?


#4

Our default source code comes with 1.5GHz as max already:


#5

Amlogic s905/x max frequency is 1.5 Ghz, it was false advertising by Amlogic, i believe that many sellers and manufacturers do advertise this soc with 2.0 Ghz as max frequency, but you can’t really blame them.

I can’t believe it took so long to discover this fraud, can’t really remember does this apply to other Amlogic soc’s, s8xx series and s912.

I did knew all of this before i bought this board, and i don’t believe it makes such a big difference, at least for me, i am using this board as some sort of lightweight pc.


#6

That’s pretty shady practice from AMLogic then, but not surprised, the product life cycle is short, competition high and profits marginal I expect, so the manufacturers will resort to any shady marketing they can to get ahead.
How much trust we should give them when it comes to long term and open driver support remains to be seen, personally I’m not hopeful until there is a truly open sourced hardware manufacturer putting out chipsets…


#7

I wouldn’t be surprised if the issue was that at 2.0GHz it got too hot and they did not want to resort to requiring active cooling. I worked on an ARM project for another vendor some years ago that ended up shelving the whole cpu due to heat issues, from what I understand.

Even at 1.5GHz depending on what you are doing you may need the addon heatsink/fan that VIM now has available.


#8

There is information that this build only works on a kernel with a maximum frequency of 2 GHz, so the s905x can provide it

The early versions of the x96 box firmware had a frequency of 2 GHz, in the newer, manufacturer lowered the frequency to 1512 MHz due to processor overheating (not really helped). Is it possible to get a core with 2GHz who improved the cooling?


#9

I would expect it is possible to get 2Ghz out of it but at what price? Pretty much the same as trying to get 4Ghz from your desktop pc cpu, sure you could do it, but not without serious cooling system and way less stability and risk of burning it out. I don’t think overclocking is really what these SoCs are all about, the whole point is they are discrete and ‘cool’, so why bother?
Still doesn’t really condone AMLogic claiming 2Ghz even if theoretically it’s possible…