Author Topic: [S7800b CPU] Official response from JXD (Read 24063 times)

DinoDirect · « **on:** December 20, 2013, 03:46:21 am »

Hi guys, following is official response from JXD on CPU issue:

JXD S7800b is not steady enough when the CPU frequency is 1.6Ghz, so we locked it at 1.4Ghz since November.

The customer may update this firmware if they want 1.6Ghz http://pan.baidu.com/s/1sj4MxPV?qq-pf-to=pcqq.discussion#dir/path=%2FS7800B%2FRK3188%201.6GHZ%20update. But we don't recommend to do so.

Please downgrade to 1.4Ghz version by firmware if the device is not steady.

XiTaU · « **Reply #1 on:** December 20, 2013, 04:52:35 am »

thanks for the support dinodirect its good someone has direct contacts to jxd im happy with the 1.42 but im interested in seeing results from the people how are not.

tito13kfm · « **Reply #2 on:** December 20, 2013, 04:53:15 am »

Thank you for this Dinodirect!

Now it's time to wait and see if Tan will integrate this in to a supercharged release.

Bargaintuan · « **Reply #3 on:** December 20, 2013, 05:08:03 am »

I'd just like to state for the record that I am not having any stability problems whatsoever at 1.6GHz. So based on my own experience, this sounds a bit dubious.

tito13kfm · « **Reply #4 on:** December 20, 2013, 05:11:49 am »

Quote from: Bargaintuan on December 20, 2013, 05:08:03 am

I'd just like to state for the record that I am not having any stability problems whatsoever at 1.6GHz. So based on my own experience, this sounds a bit dubious.

Do you have one of the devices with the locked at 1.4Ghz processor? I thought the prevailing theory was the newer units are binned lower because of some voltage leak issue or just generally lower quality chips.

The October manufactured units are indeed capable of running at 1.8Ghz and beyond.

Joe Sixpack · « **Reply #5 on:** December 20, 2013, 05:23:24 am »

Dino thanks for posting that.

It's pretty curious because I have a October unit that runs at 1.6 and I've not had any freezing or crashing.

I strongly suspect they're using sub-par SoC's in the newer production.
Maybe someone who knows more about Android like Tansoft or Skelton could take a look at the differences.. I bet they increased voltage or somehow forced the cpu to work at 1.6 on this firmware.

stpat · « **Reply #6 on:** December 20, 2013, 05:32:49 am »

Quote from: Joe Sixpack on December 20, 2013, 05:23:24 am

Dino thanks for posting that.

It's pretty curious because I have a October unit that runs at 1.6 and I've not had any freezing or crashing.

I strongly suspect they're using sub-par SoC's in the newer production.
Maybe someone who knows more about Android like Tansoft or Skelton could take a look at the differences.. I bet they increased voltage or somehow forced the cpu to work at 1.6 on this firmware.

Yes, it's a little weird that they have done something that their custom firmware can unlock, but TANs firmware cannot...

DinoDirect · « **Reply #7 on:** December 20, 2013, 05:46:14 am »

Quote from: Joe Sixpack on December 20, 2013, 05:23:24 am

Dino thanks for posting that.

It's pretty curious because I have a October unit that runs at 1.6 and I've not had any freezing or crashing.

I strongly suspect they're using sub-par SoC's in the newer production.
Maybe someone who knows more about Android like Tansoft or Skelton could take a look at the differences.. I bet they increased voltage or somehow forced the cpu to work at 1.6 on this firmware.

JXD told us that not all 1.6 devices have freezing or crashing issue. They ENSURE us all batches use the same CPU.

� · « **Reply #8 on:** December 20, 2013, 06:09:21 am »

If the components are the same and the outcome is different, then the fault is in how they are assembled - maybe JXD can issue a return policy so those with a lower build quality devices can exchange them for ones properly built?
Apart from the extra work ON EVERYONE'S SIDE, component wise, there will be no downside on JXD's side. They will equally trade every component they ship, so they can strip down the faulty units and rebuild them the proper way.

BTW, the original device could reach 1912 MHz with overclock. Not reaching even 1600 MHz due to a voltage leak is an incredible miss from a device that could do much more.

Joe Sixpack · « **Reply #9 on:** December 20, 2013, 07:05:04 am »

Quote from: DinoDirect on December 20, 2013, 05:46:14 am

JXD told us that not all 1.6 devices have freezing or crashing issue. They ENSURE us all batches use the same CPU.

Didn't say they used a different CPU I said Sub-par.. as in "low bin".. cheaper.

The RK3188 is available from rockchip in speeds (certified by the mfg) up to 1.8ghz
JXD promised 1.6ghz

They're delivering.. 1.4ghz

If they're using SoC's certified by the mfg to run at 1.6 then JXD has a problem in either design or mfg.

If an American company did this sort of thing they would be open for a class action lawsuit.

Vimtoman · « **Reply #10 on:** December 20, 2013, 08:24:48 am »

Might not be JXD's fault.
They probably designed the pcb around development IC's supplied by the manufacturer.
These would obviously be binned and checked.
When purchasing they may or may not have had an option of quality levels.
It could be the manufacturer that supplied sub spec chips.

I'm guessing that JXD have always been OK in overclocking.

What was the JXD 7300 like when overclocked.

lemmywinks · « **Reply #11 on:** December 20, 2013, 10:49:47 am »

Quote from: Vimtoman on December 20, 2013, 08:24:48 am

What was the JXD 7300 like when overclocked.

Variable, mine is at 1.3ghz but it was fine when I briefly tried it at 1.5ghz which I think was the advertised speed. The S601 I had was rock solid when clocked at 800mhz (again the advertised speed) up from the factory 600mhz.

JXD have always shipped underclocked devices, in fact I think it's pretty common with a lot of Chinese manufacturers or at least used to be. They used to combine the GPU and CPU speeds as well (S601 was advertised by some sellers as 1ghz), basically they juggle numbers and make things up to make their consoles look more impressive.

I think it's a better idea to ignore the quoted specs and just wait for some videos, if it runs the games you want then buy it, if not then wait a while.

jxdcrazy · « **Reply #12 on:** December 20, 2013, 11:56:25 am »

My 7800B is running at 1.4 too.

Actually I'm not quite worried about that since most of the games I play are old school SNES.

However, when I compare mine 7800B (1.4G) with my friend's one (1.6G), my wifi is very weak.
My 7800B has to be very close to router to get the "aceptable" signal
while my friend's device obviously get stronger signal even he was far away.

Not really sure if this came from the CPU issue or my 7800B is under QC for both cpu and wifi.

Anyone with 1.4G have the same wifi problem?

failrunner · « **Reply #13 on:** December 20, 2013, 12:51:50 pm »

1.8 is giving me no issues at all with tans firmware. Has anyone had issues with anything 1.6 or higher? O.o

Bargaintuan · « **Reply #14 on:** December 20, 2013, 01:01:06 pm »

Quote from: tito13kfm on December 20, 2013, 05:11:49 am

Quote from: Bargaintuan on December 20, 2013, 05:08:03 am
I'd just like to state for the record that I am not having any stability problems whatsoever at 1.6GHz. So based on my own experience, this sounds a bit dubious.

Do you have one of the devices with the locked at 1.4Ghz processor? I thought the prevailing theory was the newer units are binned lower because of some voltage leak issue or just generally lower quality chips.

The October manufactured units are indeed capable of running at 1.8Ghz and beyond.

I'm running stock firmware. It's not locked below 1.6GHz. No stability problems, wi-fi signal is decent.

shelikescloth · « **Reply #15 on:** December 20, 2013, 01:09:12 pm »

Is anyone having any trouble getting the 1.4's to 1.6, or even 1.8?

stpat · « **Reply #16 on:** December 20, 2013, 03:45:07 pm »

Has anyone with a 1.4 unit tried this firmware yet?

Mr.Tea · « **Reply #17 on:** December 20, 2013, 04:27:22 pm »

Installed it on a 1.4 unit about 30 minutes ago and having a problem with SuperSU loading, it says there is no su binary installed so I tried to uninstall and reinstall but still no luck.

CPU-Z comes up with 1.4ghz so I tried setcpu to see what it comes up with, now setcpu no longer loads up after the update and just crashes. i'm assuming it's a permission problem as supersu doesn't seem to have the su binary.
i'll check back when or if I figure this out.

Joe Sixpack · « **Reply #18 on:** December 20, 2013, 04:31:02 pm »

eww that's ugly, how did you update the firmware?

also try checking to see if CPUZ says there is root.

If it says yes then it could be a problem with the SU..

Apparently there is like 2 copies of SU one in the system and then the app to interface with it.. I think.
So it's possible for a device to have root but not have root app work..

There is suppose to be a easy way to fix that via ADB you'll have push a new SU to the device but im not sure the commands to fix SU this way, you'll have to try google.

Mr.Tea · « **Reply #19 on:** December 20, 2013, 04:42:32 pm »

The firmware update wouldn't show up when the image was placed on the sd card so I tried renaming it to just image.img then it asked to update, running root checker now to see but it's taking quite awhile to finish. i'll check up on ADB commands if this doesn't work.

it seems root access is a problem with this update at least for me.

EDIT- cpu-z shows it has root access perhaps it's not full root.

Author Topic: [S7800b CPU] Official response from JXD (Read 24063 times)

DinoDirect (OP)

DinoDirect (OP)