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Old 06-05-2012, 01:19 PM   #41
nosmoking
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Default Re: Samsung 305T - Video Distortions

hi,
I haven't taken the panel apart,I did email a bunch of people that should know if it's the panel ,they said it was inside the panel ,but would you tell some more about the inside of the panel and is it fixable or is it replacement time,
If you are having other problems the voltages are listed aroung the plugs on the boards ,if you have a volt meter you can check these ,they should be real close to what is written on the board,a Rat shack meter will do this if you don't have one.
Those spots on the boards that are changing color are hot spots,I got a kit off ebay for all the electrolytic caps,and replaced them,mine had 2 rubycon and the rest were samyoungs I checked the first 8 with a caps testor they were out of spec so I replaced all of them,I did notice the icons/colors were much sharper after the caps were changed,
I did try to reflow the Tcon board ,The oven is the eziest the heat gun has got to keep moving and don't bump the other parts on the board as they will move and you don't want that to happen,I took some heatsinks off of old mother boards and JB welded them to the altera chip and a few around it,I got 2 fans from old computer power supplies,and used a 9volt power supply (wall plug in style),These fans must be wired red wire to plus and blk to negitive or they won't run ,I put one fan over the altera board and one at the top of the power supply board,I use quick dry bathtub silicone and boxed the edges with plastic to make the fan fit the metal where the vent holes are,It now runs very cool,
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Old 06-07-2012, 04:13 AM   #42
nosmoking
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Default Re: Samsung 305T - Video Distortions

Quote:
Originally Posted by severach View Post
Are you saying that computer displays have a vertical line but OSD displays do not?
hi,
no with the dvI cable unplugged the screen displays the vertical line when it runs the self test and when the dvI is connected the screen shows that single light green line over the background ,the line runs from the top of the screen to the bottom even throught the black out so I think the line driver is on for that whole line...just a guess ? I have no other problem no flicker ect.
It has a great picture and vivid color....
Thanks for any he;p!!!!!!
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Old 06-07-2012, 05:17 AM   #43
nosmoking
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Default Re: Samsung 305T - Video Distortions

Quote:
Originally Posted by severach View Post
Are you saying that computer displays have a vertical line but OSD displays do not?
hi,
I have not been successful at uploading pics but will try again......nope.
The line is there during self test ,and when you connect the DVI cable and the osd is on for like google, the light green line runs from top to bottom of the visible screen ,change the picture and it 's still there it doesn't vary at all it 's like the whole line is turned on for that green color.....Everything else works ,great pictures good color no flickering,,,,
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Old 06-07-2012, 05:40 AM   #44
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Default Re: Samsung 305T - Video Distortions

I have not been successful at uploading pics but will try again......nope.

They are probably too big - try resizing down to less than 2mb and 2000x2000
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Old 07-12-2012, 10:49 PM   #45
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Default Re: Samsung 305T - Video Distortions

The problem is not the altera chip its the ribbon cables connectors lying on that logic board. They need to be resoldered
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Old 07-13-2012, 06:05 AM   #46
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Default Re: Samsung 305T - Video Distortions

I have had the 305T flicker/bad color and other distortion problems for weeks, and had Amkotron in Cerritos, Ca. repair it – took 4 days.
I did not feel comfortable dis-assembling it myself to replace capacitors, or add heat sinks, much less do the oven bake procedure.
I noticed long ago the back panel is very hot near the top. I do not believe Samsung allowed for sufficient airflow, which I think is part of the reason for failure.
After the repair, I cut out the slotted area which is sort of horizontal about 3 inches below the top of the back panel and extends almost the full width of the back panel. This amounts to 2 areas, each about 9 inches long, separated by a solid piece approx. 1-2 inches wide. I cut only those areas which are/were slotted for ventilation. Tomorrow I will also cut out the similar slotted area(s) at the bottom of the back panel near where the DVI cable and the power plug attach. Hopefully this will allow better airflow.
On my monitor, the metal covers over the circuit boards are too close to the back panel to allow for fans bolted directly. I think all I can do in this regard is fabricate some kind of duct to direct air from a fan into the bottom or top holes I have cut.
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Old 07-17-2012, 08:06 PM   #47
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Default Re: Samsung 305T - Video Distortions

Hi all, thanks for all the info!

I have a flickering 350T; I opened it up, found one bulging cap on the power board, replaced it, no difference. I'm about to recap the whole power board, but figured I'd post a video of what it looks like in case someone can give a better diagnosis. It looks perfect during the color test, then starts flickering and showing vertical lines when plugged in to a computer. This leads me to suspect that it's something that's on a board that only is relevant when plugged in (i.e. not the power board), but I think others here might have better judgement.

http://www.youtube.com/watch?v=akR5FujG2aU

Cheers!
Nevin
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Old 08-17-2012, 09:49 AM   #48
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Default Re: Samsung 305T - Video Distortions

Quote:
Originally Posted by iceace View Post
Hi,

Just a quick observation concerning the video distortions in my Samsung Syncmaster 305T Plus monitor:

- I have an ATI Radeon HD 4850 video card and by Catalyst Control Center I just adjusted Contrast -> 0 (range 0...200) and Brightness -> -5 (range -100...100) and after this pressed the 305T Brightness key to get the max brightness out of the monitor

=> no more distortion!

The overall brightness and contrast is not very good but I can work with the monitor till I get it fixed.

So just a temporary quick solution before trying any heating. Maybe this will work also in your 305T.
Hi,

As I told some time ago, I had severe distortions in my Samsung Syncmaster 305T Plus monitor.

Now I am happy to tell you that after having baked the display control card with the Altera chip at 190 Celcius (375 Fahrenheit) for 8 minutes in my oven did the magic: now it works ok!!!

It has been working ok now for some time but just to avoid the distortions happening again I added a 12 cm fan to the backside of the monitor that cools down considerably the problematic Alter chip and also the other chips on the card.

I was afraid that the plastic connectors on the card would melt down and deform during the heating but the plastic seems to heat resistant enough to stand the baking.

So my thanks to the guys who invented the idea of baking the card and/or brought it public with instructions.
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Old 08-31-2012, 11:41 AM   #49
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Default Re: Samsung 305T - Video Distortions

Quote:
Originally Posted by jeffstearns View Post
I disassembled my 305T and removed the video board. I sent it to a reballer who removed the ALTERA chip, replaced its solder balls with 63/37 leaded solder, and reflowed it. I paid about $50 for labor + shipping.

I reinstalled the video board and the monitor worked perfectly for ~48 hours. Then it began exhibiting problems again -- vertical bands of color somewhat like a TV test pattern.

I don't blame the reballer. He had no way to test his work. We both knew that, and we agreed that he'd do his best. He offered to rework the board again at no charge, but I decided that I'd try a different approach.

I sent the entire monitor to Amkotron in Southern CA (they do Samsung's warranty service, and they're nearby). Amkotron has a mixed reputation, and I was hesitant about dealing with them, but they repaired the monitor quickly and returned it in perfect physical condition. That was 30 days ago. It's been working fine ever since.

I'm not using any auxiliary cooling on the monitor. I may attach a small 12v fan and power it from the USB port, but the monitor isn't really running very warm. The hottest part of the case is the backside top at ~36 degrees C.
Hi jeffstreams
I also have a Samsung 305T with display problems. Is your 305T still working? If so, how much did Amkotron charge you for the repair?
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Old 11-02-2012, 01:48 PM   #50
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Default Re: Samsung 305T - Video Distortions

Quote:
Originally Posted by iceace View Post

I was afraid that the plastic connectors on the card would melt down and deform during the heating but the plastic seems to heat resistant enough to stand the baking.

So my thanks to the guys who invented the idea of baking the card and/or brought it public with instructions.
Let me chime in here as an Electrical Engineer:

Heating the entire board in a controlled manner was how the board was constructed originally. The process is called "reflow soldering." All of the components are designed to withstand being reflowed at least once. Baking the board in an oven is a poor man's reflow soldering, because it is based on convection (on heating up the air around the chips). Actual reflow ovens shine infra-red light onto the board, and this is only absorbed well by the metallic components, so there is not much collateral heating of unnecessary areas. In either case, the solder joints must be heated until they reach their melting point, and a new joint can be formed (as impurities boil to the surface of the liquid solder).

Happy baking!
-Adam
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Old 01-12-2013, 10:32 AM   #51
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Default Re: Samsung 305T - Video Distortions

Just baked my 305T board (used a spring clamp to make sure things were well compressed) and its working like a champ. I put a large chipset heatsink on the altera chip and left the sheilding and the back cover off of the monitor. After 15 minutes of use the heatsink is extremely hot, no wonder these chips come off the boards.
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Old 01-18-2013, 08:31 AM   #52
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Default Re: Samsung 305T - Video Distortions

Installed with a heatsink which gets pretty hot after a while
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Old 02-10-2013, 01:16 PM   #53
C0rnholio
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Default Re: Samsung 305T - Video Distortions

Found a 305t for a good price. Looks like it has the mod heatsink + fan made by the owner. I don't know much info about it's history, nor have I seen it in "person" to inspect what kind of mod was exactly done to it.

Is it safe to purchase a monitor that was previously "baked" or reballed? After re-balling I know the problems will just come back if you don't cool it but w hat's the expectancy AFTER doing the re-ball + cooling added? Anybody had problems after adding the cooling system or this is pretty much safe and future proof ?
I've had some trouble with the famous nVidia BGA issues with some of their cards and I know the re-baking was due every month.

I don't want to purchase a monitor I have to "bake" every 2 weeks

Thanks
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Old 02-10-2013, 04:50 PM   #54
jetadm123
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Default Re: Samsung 305T - Video Distortions

Quote:
Originally Posted by C0rnholio View Post
Found a 305t for a good price. Looks like it has the mod heatsink + fan made by the owner. I don't know much info about it's history, nor have I seen it in "person" to inspect what kind of mod was exactly done to it.

Is it safe to purchase a monitor that was previously "baked" or reballed? After re-balling I know the problems will just come back if you don't cool it but w hat's the expectancy AFTER doing the re-ball + cooling added? Anybody had problems after adding the cooling system or this is pretty much safe and future proof ?
I've had some trouble with the famous nVidia BGA issues with some of their cards and I know the re-baking was due every month.

I don't want to purchase a monitor I have to "bake" every 2 weeks

Thanks
I know some will differ with my opinion, but I'll offer it anyway: If it was "baked" in someone's oven, you don't know what temperature they baked it at and for how long. This method is used by many that don't have access to reballing equiptment and tends to be a hit or miss method for restoring your video card. Personally, I would avoid buying, since all components are heated up, which may fix the video chip, but may also shorten the life of other components on the board. People will use this method to restore a laptop, video cards, etc. Once they get it working, they quickly sell it off to someone else and it becomes their problem. The problem seems to resurface after a while and you can only rebake these boards so many times.

Re-balling is the professional method of restoring the card as you're only working on the chip in question and not heating up the entire board. This method is not foolproof and relies a lot on the equiptment used and the technician's skill level. Helps to find out about the reputation of the shop doing the reballing.

Re-balling and the additional cooling fan is the way to go, but as you probably already know, it's always difficult to predict how long the "repair" will last.
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Old 02-10-2013, 09:10 PM   #55
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Default Re: Samsung 305T - Video Distortions

Thanks for the answer jetadm123.

Anyone have any idea how much would a chip board cost these days ? I would like to have all my exits covered and know what I am getting into, in order to know if this is worth the risk. The monitor's price is about 350$ and seems to be working fine as is with the mod.

Also there are a lot of guys out there that reported that without the mod - the chip is at about 100 deg Celsius and with the mod done, it goes up to 45-50 tops. Any idea how they measured this ? Is there an internal temperature sensor or they used an external thermometer of some sort ?

Thanks
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Old 04-11-2013, 02:33 PM   #56
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Default Re: Samsung 305T - Video Distortions

Just registered to thank you guys for the tips. Seems I've managed to fix my 305T+ according to your suggestions. Baked for 8 minutes in the oven, put a chunk of bulk aluminum on to of the chip to apply some presure while baking. Paid almost $20 for the thermoconductive epoxy to glue the heatsink to the altera chip but if it really solves the problem it will be way worth it. I decided to glue the fan to the back plastic instead of screwing it to the heatsink. I didn't feel like putting more preasure onto the chip.
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Old 05-23-2013, 06:57 AM   #57
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Default Re: Samsung 305T - Video Distortions

Hi there!

First wanted to thank all of you guys for this great valueable resource of vast problem fixing knowledge ... unfortunately I've got the same 305t (plus) problem as many here had/have. After nearly 3 years the monitor already exhibited the same problem (green "pattern" noise/lines) and got repaired/replaced within warranty. But now a good year later, after warrranty ran out, the same problem re-appeared.
From what I gathered I'm very certain it's the same Altera chip/solder problem...

While I'm still a little "afraid" after reading all the "success stories" I want to try the baking procedure now and see if this will work.

Just wanted to ask first... I gathered that I have to disconnect everything from the TCon board (the one with the Altera chip on it) .. so all I got is the bare board. Then I put it into my kitchen oven.. hm should I chose "air ventilation" or "top bottom heat" only? Set that to 190-200 degrees (celsius) .. put the board in and let it bake for 8-10 minutes, right? No "pre heating" (waiting until the oven reached full temp), right?
And it seems most people fix some aluminium foil/clamp contraption to the Altera chip so it really "stays" in place while baking...
Still afraid it might bake to long or something.. could 10 mins be too much already?

Thanks for any tips!!!

Last edited by SoerenM; 05-23-2013 at 06:58 AM..
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Old 05-23-2013, 02:10 PM   #58
SoerenM
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Default Re: Samsung 305T - Video Distortions

Thanks to several guys helping out via PM - thanks so much!

It worked!!! Disassembled the 305t plus, removed the board with the Altera chip. Baked it in a normal convection oven that was pre-heated to 200 celsius (baked for 8 minutes). Let it cool down for over an hour. Reassembled and reconnected... et voila - perfectly working monitor again!
Priceless! =)
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Old 06-14-2013, 11:42 PM   #59
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Default Re: Samsung 305T - Video Distortions

Howdy,

I'd just like to add that the oven reflow method worked for me as well.

My 305T+ initially just had a discoloured vertical stripe about 1.5inches wide on the right side of the display. After a week it then started to flicker and there were more vertical stripes of different colours as well.

I removed the board with the Altera chip and baked it in a preheated oven at 200C for 9 minutes. I then opened the door to the oven and let the board cool in there so as not to disturb it while the solder was possibly still molten. Once the board had cooled I reassembled the monitor and it was all good.

I should note that I did all this less then 30min ago so the problems may reappear, but it's working for now. I'll certainly come back and update this post of there are any further developments.

Thanks everyone!
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Old 06-15-2013, 05:46 PM   #60
jetadm123
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Default Re: Samsung 305T - Video Distortions

It's the heat generated by the Altera chip that causes the problem to begin with. If you don't use something, like a fan, to cool it down with, then you'll be seeing the problem re-occur a lot sooner than you think.
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