Gfx Performance Of C700

[rafm]

I have just moved from 5500 to c700 and I am not so impressed with the graphics performance of this clamshell model.

I suppose that doubling the resolution without upgrading graphics hardware is one reason for poor performance (I guess all Zaurii are still running ATI'a I100 chip).  But people also complain that the performance of c700 is much worse than that of c760 and latter models. Does anyone know what has been changed from c700 to c760 so that the latter runs much faster? Memory? Gfx chip? Is the Gfx performance of c760 matching 5500?

[lardman]

without upgrading graphics hardware is one reason for poor performance (I guess all Zaurii are still running ATI'a I100 chip).

Only the C7x0 machines run with this chip. Not sure what the 5500 uses, but it's something else.

But people also complain that the performance of c700 is much worse than that of c760 and latter models.

Are they talking about graphics or just general performance? Three possibly reasons - it really is worse for some reason, the cache errata bugfix is slowing it down, less system memory.

Is the Gfx performance of c760 matching 5500?

I think the major issue is that the screen area is 4x as large - this is what's causing your troubles IMO. Try running your movies/etc. at 320x240 and see how they go (other than very small  )


Si

[Mickeyl]

The major reason for perceived slowness compared to SL5500 is that while having a processor that hardly is faster you have

 * many more pixels to draw, and
 * code from an ancient compiler born before people even thought about an xscale CPU.

[rafm]

So one more questions: is there a significant difference in performance between OSes and kernels? In particular is OpenZaurus faster in than Sharp/CackoROM (because of a newer compiler or better libraries)?

[Mickeyl]

Overall, OpenZaurus should feel a fair bit faster than cacko, although drawing surely is slower because we don't utilize the w100 accelleration yet.

[seinfield]

I have a c700 and after adding a 1Gb sd card and create a 128mb swapfile, it is running smootly.
When i had only 32 of ram it was too slow and sometimes crashed. Now with a 128mb swapfile, no crashes at all.


Regards.

[jchung]

The C700 runs the PXA250 which was known to have a memory bug that was restricting access of full speed of the memory..

C750 and above use the PXA255 chip which fixed that problem..