Howdy folks.


I'm considering this as my next pj., but I have some questions:

1. Rainbow effect... how bad is it, and in comparison to other pj?
2. Can it really do 24Hz @ 4k, I read that the DLP 0.66 4K UHD DMD (https://www.ti.com/lit/ds/symlink/dlp660te.pdf) operates @ 120Hz so in order to do 4k it oscillates 2x and consequently can only do 60H.
3. Would you still buy it again?
4. What other UST pj have you eye'd up? The Optoma P1 is at the top of my list, but I dislike shopping retail for warranty and bargaining... whereas Dell is usually just a web chat away and they've been good to me.

Thanks

I think I would buy it again.

Some of the caveats are with any projector. Setting it up, buying the screen, RBE, etc.

1. RBE is about on par with the BenQ 2050 (iirc) I had. Where I notice it at first, then I kinda get used to it, and eco mode helps, also sitting further away helps =P.

2. Hmm I haven't tried 24P, sorry. Think my shield auto detects it at 59.940 and I simply manually set it to 10 bit yuv 420 2020.

3. I would, 4k on a 100' screen is awesome. I think 4k is hard to appreciate until you have a large enough screen. For me, at 10-12 feet away, 100 is pretty perfect to actually want everything in 4K now.

4. Haven't tried another, and honestly the CLR PET screen is what makes it. It's like having a non-glossy giant monitor, that is totally usable in all but the harshest direct sunlight. My old benq was not usable with the house lights on. This still looks amazing with the lights on! That's a big deal. I mean even a TV is not fun to look at when the sun shines directly on it, so this brings it up to par.

This projector has almost no settings, it's made for business use and it shows, I wish it had options but it doesn't. When it detects HDR content, it forcibly puts itself out of eco mode (hello slight RBE!) and while looks good, it's a bit jarring to suddenly see everything so saturated! Not sure how I feel about this yet, maybe if it had more options these quibbles could be mitigated. If I turn HDR off on the projector, my shield no longer detects it as a 4K unit and goes to 1080p!

Hi,
So I went ahead and bought this bad boy AS IS for Parts for a steal on eBay - well basically it works except it has the white dot syndrome which is indicative of a DMD failure.. (it's out of warranty)
So I went ahead and tried to open this baby up and low and behold it ain't like opening a PC.. This thing has multiple motherboards and it's complicated! I can't find any schematics online or anybody else who opened one up..
Before I go any further would anyone have any idea where the DMD chip resides on this thing? I used to be a PC tech so i'm not afraid to get into the belly of the beast..
Thanks in advance. Best, Mike

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The DMD chip should be to the rear of the lense assembly. I had to replace one in an old Dell years ago and that's where it was.

Mine was mounted to a cooling plate like you would find in a computer and with thermal paste, just like a cpu.

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very cool and well done!

i owned a s718ql for a short while but in the end returned it, but when i had it i wanted to do a few things to it such as replace the chinese gui with an english version (which i was able to do by rooting it), and change the dell splash screen, which i was never able to do.

anyway, at the time i contacted coretronic, the manufacturer of the s718ql, to see if there was any way i could get my hands on a service manual and was flatly told no, by all three folks i sent an email to, maybe you can have better luck:

https://vsbg.coretronic.com/business/95-u50k-platform

https://www.ravepubs.com/infocomm-20...-home-theater/

Thanks! Wow that gold colored one looks cool in the link! I was wondering about coretronic I saw that name tossed around and had no idea. I thought Dell made these no wonder why it's so hard to service thru them. their service tags & express codes don't even register on dell.com lol
Will try and see how far I get
_______________________________
very cool and well done!

i owned a s718ql for a short while but in the end returned it, but when i had it i wanted to do a few things to it such as replace the chinese gui with an english version (which i was able to do by rooting it), and change the dell splash screen, which i was never able to do.

anyway, at the time i contacted coretronic, the manufacturer of the s718ql, to see if there was any way i could get my hands on a service manual and was flatly told no, by all three folks i sent an email to, maybe you can have better luck:

https://vsbg.coretronic.com/business/95-u50k-platform

https://www.ravepubs.com/infocomm-20...-home-theater/[/QUOTE]

Thanks! I think I see it.. probably it's under where all the cooling apparatus is!

SO I was finally able to catch this slippery sucker! @Johnny14o you were right! it's below that heat sink apparatus. not really sure if I actually see some damage in the mirror or if it's possible this chip may still be good! .. I noticed alot of thermal compound paste that appears to have seeped or bled into the actual socket.. not sure if that's supposed to be there where the pins go in. Does anyone know if I should try cleaning out the socket, re-seat the DMD chip and see if it works?
update: I just checked out this video and it appears mine is bad, the mirror is definitely not perfect, one side of it is blurred/uneven - probably not even gonna waste my time putting it back, just gotta wait now for Texas Instruments to get these bad boy's back in stock, they are no where to be found! If anyone knows where I can get one please let me know (part #: DLP660TEAAFYG)
Thanks again!

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From what I see there is a visible heatsink in your photos.

From my experience, all DMD chips need some fair amount of cooling so the device will have a big heatsink that resides on the very back of the DMD chip.

If you can disassemble everything and reach to the screws holding down the heatsink on the DMD board, the you will be able to reach the actual chip.

EDIT:
Sorry, I went ahead of myself and didn't read your following post that you have moved ahead already.

It is basically an IC so places like Digikey or Mouser will have them.

But from a quick look at Mouser I think they say the specific product is discontinued or End of Life.(?)

I might be totally wrong though so the best way to check is to contact Mouser directly and ask them.

However, if I were you, I would clean the socket and the pins from the old paste as thourougly as possible with a capable solvent like WD40.
Then reseat the chip carefully with clean new paste and fire it up.
Just to make sure.

These things get pretty hot in operation and the continuous thermal stress can possibly unseat it from its right place.
They are made to work under heat, but with proper dissipation.
If the paste had gone bad, maybe a new clean re-install might give it life again.
Just maybe.

Just by looking at the DMD chip you might be able to see the problem. When I had an issue, there was a burn on the corner of my chip... Under the right light you can see it...

I would check like that first, then decide if you want to reseat and retry..

Also, what is the model number of your projector? In some cases, searching for the DMD chip is better by the model number because there could have been multiple DMD chips that could/have been used during the production of the projector. Usally the latest version of the DMD chip having the fewest issues and therefore your best bet for replacement.

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wow Thanks for the advice! I'm gonna try and clean it up and re-install just to make sure..
NOBODY and I mean NOBODY has this chip - and I even checked with TI themselves and they told me they are on backorder until mid December. I'm thinking maybe they had some issue where alot of them were failing and they had to re-engineer ?
https://e2e.ti.com/support/dlp/f/94/t/857738

Yeah, that's quite possible.
But also check all possible physical connections.
The boards are usually sandwiched with each other and the pins connecting them might, just might, need to be reseated and sprayed with some contact cleaner.

I say that because from my experience with DLP PJs worked extra long hours (my HT2050 is nearing 30000 hours), I see the actual DMD as the less likely failure suspect. I've never seen it being damaged yet.

I suppose, there should not be many things that physically can kill a DMD.
The list should be short: excessive thermal stress from the actual light engine and inadequate heat dissipation from the cooling system.
So basically, other than other that, the mechanical hinges those mirrors are hanging from, should be heavy duty and long life.

Another possibility is that a nearby IC which communicates with the DMD to be blown.
Look for things like the scaler board and any other visible passive part that might be looking suspect.

A schematic or a Service Manual will give you insight.

In the end, if you single out it is the DMD chip, I am afraid it can be pretty expensive.
Is it worth it to invest in such a part?
I know how lovely it feels when you refurbish a device, but it is always a matter of cost as well.
Hope you can figure it out!!

By the way: Mouser also lists the part as Obsolete.
Bad news I am afraid mate..
That is the worst thing it can happen to a service project.

thanks again, according to TI the chip will be made it's just a matter of time.. another option is to cannibalize another unit that utilizes this chip. There are 2 other projectors so far I know of that use this particular DMD.. the optoma uhd60 & Vivitek HK2299 and I have them both on constant search with eBay for an "as-is" for parts unit.. I picked up this Dell for $800 so even if the chip was $1000 it would still be worth it.. But I know the chip will be less because it's actually available as a kit - part of a reference design evaluation board here for $1037: https://www.digikey.com/products/en/...&newproducts=1

I'm almost 100% sure it's the DMD because I can see the problem right in the mirror.. and according to youtube if you search for "white dot dmd" - it appears they fail all the time..
Schematic / Service manuals are no where to be found either, another poster mentioned to get one here, he tried and they refused to give him anything like they're top secret or something lol: https://vsbg.coretronic.com/business/95-u50k-platform

I'll keep you posted on the progress!

Awesome, thanks... I love teardown pics.

@All ; I've been losing the Dell/Coretronic HW lottery.
1st unit made a lot of noise, well 47dB in eco mode to be exact, so I eventually got a replacement. The new unit was 8dB quieter (still very loud) but exhibited blurry top corners.




The final mirror has some cogs on each side, does anyone know what they do? I assume they shape the projected image, but some verification would be most welcome.

Also for anyone considering this PJ, the rainbow effect is quiet prominant and always present when blinking your eyes if there are any white scenes on screen.

Also HDR is a total joke; poor color and 67dB of noise to go with it.