Asus VK266H Monitor rebuild.

[JoseyWales]

I have to replace the caps on the power board. The main board caps look ok and only one on the power board shows signs of swelling.

the caps on the board are:
3- 680uf 25v
2- 1000uf 16v
3- 470uf 25v
1- 470uf 16v

It is one of the 680's that has the swelling and I belive it it the cause of the problems with the monitor.


My question is just what caps to replace them with. I want the best I can get for the job but I am not sure which ones to order.

The main board.. All the caps look good on it.

[selldoor]

Suggest you replace them all on the ps board - look to be Ost which are not great.
Order panasonic FR FM or FC in that order from digikey - check that the physical size will fit Width AND height.

Many regulars would prefer pics posted using manage attachments rather than in line.

[JoseyWales]

I ordered all 9 for the power board. I went with the fr ones. Pretty sure I got the correct ones based on size. all are 10mm round so that made it a bit easier.

[grtessman]

I have to do the same rebuild. And wanted to ask a few questions if you don't mind... How did your repair go? Was everything fine after replacing the capacitors? I have the exact same problem, same scenario you described. I haven't yet taken mine apart but am looking to order the same capacitors. Do you happen to have the part numbers you ordered from digikey? I'm uncertain about the heights until I disassemble. I wanted to see if doing this manually or buying a rebuilt 715G2594-2 board would be better.

Thank you!

[jajamumu]

Hi , I'm from France. I have discoverded this very interesting forum
I have VK266H screen and when I switch it on it have a very important vertical instability becoming stable after about 1minute. Does somebody know the cause . Does somebody have the service manual? I would appreciate a lot.
I changed two caps but it's unchange . I tested the two voltage regulators 278R15 and one gave me some strange results but anyway the screen is ok after a while . When a failure appear for a short time only I think that I have better wait for a definitive failure to be able to find the cause.
I would appreciate any advise on this.
jajamumu

[Rtech]

To chase an Intermittent fault,is one of the hardest to ty and do.I would continue to use it as it is, until you have more and constant fault information, to try and find the problem.

[selldoor]

You could do some testing when it is good and when bad - might give a clue.
As would a picture of the fault- have you removed cleaned and reseated all cables

[budm]

"I changed two caps but it's unchange . I tested the two voltage regulators 278R15 and one gave me some strange results but anyway the screen is ok after a while ." Caps and regulators on the main logic board or the power supply-inverter board?

[jajamumu]

If some body have the service manual I would appreciate to share it.
Thanks a lot. Anyway ,when the failure will be confirm I'll change all the caps as I know the original caps are never the best .....and also to get an obsolescent timing .that's the way for making new units and get them off just after the the time of warranty.

[Gingko]

Hello,

I also had capacitor problems with a similar monitor (VW266H instead of VK266H, which is the same without webcam). The symptom was that the monitor needed about 2 or 3 minutes before powering up, and during that time, the power led was blinking about every 5 seconds, like if the monitor was continuously "rebooting" at that rate.

This monitor, of course, uses the very same power board as above, with the very same capacitors. But in my case, the swelling capacitors were the two 1000µF ones.

As I my job involves me in working with electronics components, I had no trouble in finding replacements among our stock, so I replaced these two ones along with all four 470µF (not the 680µF so far because they have to be ordered).

Now, right after this replacement, my monitor seems to work perfectly.

Gingko

[Gingko]

Originally Posted by jajamumu

If some body have the service manual I would appreciate to share it.
Thanks a lot. […]

… and by the way, better late than never, here is a copy of the service manual that I have.

Gingko

[Boro Guy]

Hello,
Like Gingko, I too have fixed my Asus VW266H based on the information in this thread - replaced 5 caps on the power board yesterday, now all is good again!

Thanks very much for the inputs from others, to this thread.

[SpiderWaffle]

My VW266H is failing too, I get a similar power up issue as this:
https://www.youtube.com/watch?v=JqHGihXIzaE

I've found after slowly cycling through the display modes (HDMI, VGA, DVI, ect) 2 or 3 times, it's been progressively taking more cycles, it will eventually display correctly with no visual problems.

However... It causes my speakers to create MUCH more power humming noise, and my other display to flicker/pulse noticeably at about 1HZ(and much worse when it's displaying more white). Also, my video card will hum as well. All of these symptoms gradually get less serve the longer the failing VW266H is left on. After the VW266H is off for awhile it starts back up again and this has been gradually getting worse.

Obviously failing Caps in power board, would there be any others to replace too, or just the bad ones in the power board?
Thanks so much!

PS. sometimes it's had this one yellow vertical line permanently stuck in image, it showed up after about 2 years, then went away completely for about 3-4 years, now sometimes shows back up again. It will go away completely after monitor is in use for a few hours or less if it does show up at all.

[momaka]

Originally Posted by SpiderWaffle

Obviously failing Caps in power board, would there be any others to replace too, or just the bad ones in the power board?

Just replace every capacitor on the power board except for the very big one, since it rarely fails.

The capacitors on the video/logic board *usually* do not go bad as often as the ones on the power board, but if you feel like it, you could replace them as well.

Here's in an updated list of suitable capacitors you can use in the power supply:

Manufacturer................................Series
Nichicon ................................ PW, PM, PS, PJ, PV, HE, HD, HW
United Chemicon (UCC) ............ KY, KYA, KYB, KZE, LXV, LXY, LXZ, KZH, KZM
Panasonic .............................. FC, FK, HFQ (old stock only), FR, FM
Samxon ................................. RS
Rubycon ................................ YXJ, YXG, ZL, ZLJ, ZLK

[SpiderWaffle]

To my dismay I don't see any bulging on any of the caps on the power board. Do you see anything wrong with this power board?
Should I still replace all these caps?
Thanks

[budm]

Bad caps can look normal but the capacitance may have drop or the ESR are high, you cannot really tell by using visual inspection alone.

[jetadm123]

If those are CapXon caps on the mainboard, I'd definitely replace them.

[SpiderWaffle]

Originally Posted by jetadm123

If those are CapXon caps on the mainboard, I'd definitely replace them.

Yes, the mainboard has 12 little ones, and 2 470uF ones, all CapXon. You'd replace all of them? They also show no physical signs of wear.

The ones on the powerboard are all eLite.

[jetadm123]

Yes, I would replace them. As budm said, caps don't have to look physically bad to be bad. And CapXon caps are of low quality and should be replaced on sight.

[SpiderWaffle]

Alright, does this seems like a good buy on the caps then?

http://www.amazon.com/Asus-VK266-Mon...K266+capacitor

Also I can desolder and measure them individually and only order replacements for ones that don't measure well, is this a reasonable idea or just do the whole lot?