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Electronics => Repair => Topic started by: m3vuv on February 24, 2022, 08:58:35 pm

Title: lappy screen replacment confusion
Post by: m3vuv on February 24, 2022, 08:58:35 pm
Hi all,i have 2x dell inspiron 1720 lappys with dead ccfl backlights,i found this on fleabay,can it be right? or just a missleading con listing?,to me it reads as a led backlit lcd screen?.:https://www.ebay.co.uk/itm/362527723495,surley you cant replace a ccfl backlit screen with an led backlit one without mods to the lappy,ie inverter etc?
Title: Re: lappy screen replacment confusion
Post by: abdulbadii on February 25, 2022, 06:32:50 am
Too few now care CCFL as its advantage just a more even light, or more even over a lager size LCD.. with
downside
- CCFL backlight requires a higher voltage
- CCFL backlight requires an inverter
- Contain mercury, as many countries limit or bans CCFL
- Shorter life time then LED. An estimated 21000 to 30000 hours
Title: Re: lappy screen replacment confusion
Post by: Whales on February 25, 2022, 10:26:06 am
Some laptops came with a choice of screens, perhaps this (or an equivalent) was an option?  The inverters were often on separate boards, ie removable. 

(Definitely don't use the inverter on the LED backlight!)

Best I can suggest is contacting the seller and asking.
Title: Re: lappy screen replacment confusion
Post by: m3vuv on February 25, 2022, 06:02:23 pm
Well,i have messaged the seller twice,but no reply,did you look at the listing?,i know the pro's and con's of ccfl v's led but need to know if the screen listerd is going to be compatible with my inspiron pp22x,as far as i know there was never a pp22x produced with an led backlit screen.
Title: Re: lappy screen replacment confusion
Post by: Whales on February 25, 2022, 09:21:46 pm
I have no way of telling just looking at the listing, sorry.

* Pinout and protocol for the main cable needs to be the same
* Motherboard needs to support a non-inverter power supply (both in hardware connectors & firmware)

With more modern laptops and screens you have similar issues with the eDP connectors and pinouts.  Some are the same, some are not.  Different motherboards/graphics support different numbers of eDP lanes, for some screens you need more.
Title: Re: lappy screen replacment confusion
Post by: flolic on February 25, 2022, 09:32:36 pm
That screen will not fit.

You need something like this: https://www.laptopscreen.com/English/model/Dell/INSPIRON%201720/ (https://www.laptopscreen.com/English/model/Dell/INSPIRON%201720/)
And that's next to impossible to find...