Bad series nvidia chip ?

[primoz1]

On two laptop hp pavilion dv9000 i gor same problem, after reball wont show any picture, befroe show white or change white to gray to black colors on screen and not work on external monitor.

So i Suspect to bad series BGA chip, is someone familiar what marks on chip has bad seria ?

[Mad_Professor]

Re: Bad series nvidia chip ?

Sounds like you got the nvidia underfill problem.

http://www.theinquirer.net/inquirer/...hips-underfill

http://semiaccurate.com/2010/07/11/n...fill-problems/

Your only option is to replace the chip with another one, then place copper shim on it before adding the heatsink back on.

Any series between 8x00 to GTX 5x0 series.

[primoz1]

Re: Bad series nvidia chip ?

Hi. So must get new chips, but what series is OK. If I buy new from this series is possible to die again after few month and then repeat whole thing

[rievax_60]

Re: Bad series nvidia chip ?

How does the shim improve the reliability?

[primoz1]

Re: Bad series nvidia chip ?

I got bad expirience with this copper shim, I not say that is total useless but in most cases wont help, or help if heatsink dont seat enough on chip core, otherwise I dont see benefits of them.

[severach]

Re: Bad series nvidia chip ?

Copper shims are fine so long as they are the right thickness so that the heat sink lays flat. Too thin and the heat sink has too little contact and the shim may fall out. Same with too thick except that the chip is at risk of damage from clearance and spring pressure.

A feeler gauge will let you zero in on the right shim thickness for your application.

[BigTroll]

Re: Bad series nvidia chip ?

I had the same thing happen to my dell inspiron 1720, bad 8600gt, luckily it was on a seperate module and i found another card on ebay for under $30 shipped, now its good as new. my friend also has a dv9000 with the 6150 and it suffered a failure.

[mattbrad2]

Re: Bad series nvidia chip ?

promoz1, your problem could be with the video ram. Do you have separate video ram on this model?

And yes, I'd recommend a copper shim. DONT use a penny. The correct thickness is paramount.

[ratdude747]

Re: Bad series nvidia chip ?

Don't shim it. From my experience the shims aren't that much better and not worth your time.

The problem is that there is a certain tolerance in the dimensions of the cooling HW that the pads are meant to take up. A shim is rigid and doesn't allow for such compensation.

In addition, often times the chips with pads have the HS mounted only on one side of that chip. Such configurations work best with pads, as in order to get the flush level of contact needed by a rigid system, you need the pressure holding down the heatsink on both sides.

What I DO suggest (after replacing the blown chip) is upgrading pad materials. I fogot the brand/product but they do make a silver pad material that can be cut with a knife to size and has thermal adhesive on one side. It's also good for GPUs and the like with those white pads that often go bad... My stash was part of a trade so I don't know where it can be bought.

[primoz1]

Re: Bad series nvidia chip ?

Hi. jes is separate ram blocks on both boards, but what would you do in my place ?

In few(diferent boards) times I just reflow this ram blocks with AOYUE hot air station, and then work ok, sometime must reball the RAM chips too, but I dont know if I got stencil for all models.

you're right, thickness of copper or aluminium plate is important, but in previous post I got phonecall an forget say that, I spend 3 minutes to modeled shim in my favorite 3D program and then forgot complete why I do this