China 13.3" netbook (Allview D425) backlight issues

[Th3_uN1Qu3]

A friend of mine bought this p̶i̶l̶e̶ ̶o̶f̶ ̶t̶u̶r̶d̶ netbook for parts, but he then decided he wants it fixed. It's got an Atom D425, 2GB DDR3 and a 320GB HDD which got swapped to a 32GB SSD (China's finest too, of course).

The original issue was odd-coloured display with lots of horizontal lines striking thru it. Taking it apart revealed 2 bent pins in the LVDS connector. Someone's been here before and attempted to do something. Likely they tried to pull that wifi cable that was hanging out the hinge back in place. Easy fix.

Now another issue has surfaced, namely the backlight. It will work fine for a few seconds to a minute, then start strobing like crazy then finally settle to a dim level, only strobing occasionally. Brightness controls will still work, just that it's "dim" to "off" instead of "bright" to "dim". Unplugging and plugging it back in makes it come back, then it does the same thing. Also the backlight will either not come on at all on battery power, or it'll work for a few seconds after it's unplugged, then turn off and stay off.

My first impression to the construction of this thing was positive, it's cheap, but better than i expected. I'll take it apart again tomorrow and see what i find.

[Th3_uN1Qu3]

Re: China 13.3" netbook (Allview D425) backlight issues

Fixed. Loose LVDS cable. That connector it plugs in is absolute garbage.

Anyway. I like the thing so much i might even get one for myself as they're dirt cheap. There is potential for quite a bit of modding inside.

One thing that i don't like is the battery life - not because the battery is crap, but there have been exactly zero f***s given for power management in this netbook. The Atom CPU always runs at nominal clock and voltage, no reduction is possible via BIOS or software. Hence why the large copper cooling plate most likely... At least there is working overtemperature protection.

[sopik78]

Re: China 13.3" netbook (Allview D425) backlight issues

Good job. I have similar problem with Asus Lamborghini with LED backlight, haven't fixed it so far. Too lazy spend more hours on it.. LVDS cable changed, power on lvds conector seems to be ok, but have no other 12,1" 30-pin lcd screen for trying to change, so it's undone for that moment.

[Th3_uN1Qu3]

Re: China 13.3" netbook (Allview D425) backlight issues

Played with it some more. Turns out the Atom D425 is a "nettop" (small desktop) processor, not a mobile one. It has higher TDP and lacks of support for Speedstep and EIST, so this is a processor limitation not the designers of this board being lazy. Since this is a generic unit, i wonder if an upgrade of the BGA processor will work. I have the stencil for it so maybe i will try when i get mine.

This Atom D425 is a single core processor with HT, there is also the D525 which is a dual core with HT, with just 13W consumption as opposed to 10W. Then there is the N series, which has the "mobile" counterparts with lower TDP.

I have also replaced the wireless card, Broadcom BCM4322 with a Realtek RTL8723AE. Previously the wireless range was all of 5 meters. With 3 bars of signal it dropped the connection... Now it's much better, i can walk around the place with it no problem. And i got free Bluetooth too as it is a combo card. It still feels like it could use the second antenna though (it only has one).

I am going to be keeping this WLAN/BT card though, i'm not throwing that in for free.

[dellxps15]

Re: China 13.3" netbook (Allview D425) backlight issues

how much is this cinease netbook?
and 13.3 is big to be called netbook, almost a notebook

[Th3_uN1Qu3]

Re: China 13.3" netbook (Allview D425) backlight issues

Well they call it a "Note Book". But it has netbook specs so i call it a netbook. It was ~$280 new in 2011, now you can find it for $80-$100 used in good shape.

What i really like about it is the screen. It has 1280x800 resolution and very good viewing angles. It is a TN panel but a very good one. Horizontal viewing angles are almost 180 deg! A $2500 Sony Vaio i worked on a couple months ago had a worse screen than this. It also weighs just 1.4kg.