Sony PCG-7121M VGN-NR21Z Display screen problems

Sony Vaio colored stripes

Sony Vaio colored squares

A Sony VGN-NR21Z NOT functioning

A Sony VGN-functioning NR21Z

And here I am to present a successful repair of another Sony Vaio PCG-this time a model 7121M who suffered, like many other PC fitted with NVidia graphics cards, a defect of overheating that literally unsolder the graphics processor on the motherboard.

Mock Up:

Sony Vaio PCG-7121

Defect / fault:

Sony Vaio With Defective Video Card, Does Not Turn On Or Artefizi Presents On The Screen

Details / symptoms:

  • The PC often comes on. Sometimes when you start showing on the screen, since the BIOS logo, some graphic artifacts such as letters (usually an ‘a’); Subsequently reaches startare Windows but the screen shows graphical artifacts vertical (vertical lines).
  • In many cases, the most serious, the PC does not show anything on the screen, although you feel the fan on.
  • In many cases in the resources panel rather than the video card NVidia GeForce appears the classic ‘Standard VGA': this is because the system is able to detect the card but not perfectly so do not load the drivers and active graphics card base

A Sony PCG-7121M starts with problems NVidia GeForce

Why it happens?

Simple: the Nvidia mounted on PC until a few years ago (and also on the XBOX 360 older generation) technology had a poor compared to their power. Result: a lot and soon began warming problems. That even if you kept carefully pc: not escaped. Moreover, the problem is also given by the solders who have recently undergone a revision in the application because of the lead: no talk then of tin-lead (lead) that seem to create many problems of breakage in particular conditions.

Some of these GPU after a while begin to virtually dissaldarsi. Is there a way to solve totally definitive and is basically making a risaldature graphics processor. The process is called reballing (recreation balls of tin) followed by reflow of BGA (risaldatura). The work is to ‘unstick’, clean from the old pond, stick ‘of the new (in the form of micro balls) and resolder: no easy task and often delegated exclusively to professional labs.

In some cases a reflow without reballing okay (less invasive technique using only the heat) but the reballing is more definitive.

In fact both procedures, if done properly, give excellent results ..

But before we talk about Sony warranty.

Extended warranty from Sony:

Meanwhile, check the warranty: Sony fact on some products has extended the warranty to 4 years. Call the call center and the serial indicated below, only they will tell you if it is covered by warranty. If you have no receipt no problem, they can do the same in this evaluation.

How do you solve?

The project involves the risaldatura nVidia graphics processor with restoration of all welds. The procedure is carried out via the preheating plate (preheat) and high precision machinery to infrarosssi or – if you are endowed with excellent manual – with the aid of a soldering station air and special nozzles. Personally I have tried both and I can say that after a lot of experience I can work quietly with my trusty hot air station and many other components and quality tools.

Below are some steps I followed to repair this model.

To be noted that the information given here can also be applied to other laptops with the same defect.

We begin with the completely disassemble the Sony, coming to the motherboard:



Motherboard Sony Vaio with NVidia GeForce


We remove all remnants of pasta and we clean the 3 processors is completely covered by the copper radiator is the radiator itself.

Completely detach the motherboard from everything else and concentrate now on the GPU Nvidia GeForce:


reballing NVidia GeForce Sony Vaio


Here are some sequences that show the steps for a reball.

We start by warming both the motherboard through the preheat plate that with the hot air, watching the whole with a thermocouple.

preheat reballing sony acer asus toshiba PCG-7121M

Arrived at about 220 °, after a few minutes, we can with the appropriate pomp aspiring disconnect the processor from the motherboard.

reball hp acer sony PCG-7121M

Next step is to eliminate, with the help of the braid, soldering iron and flux, the whole pond residue being careful not to take away even the tracks ..

reballling acer asus bga Sony VAIO PCG-7121M

Now let’s work the processor ..

reball bga sony acer asus toshiba

Cleaning with the previous method ..

reball bga sony acer asus toshiba

After cleaning up to the new flussante..questa time with different characteristics from the previous one ..

reball bga sony acer asus toshiba

Now select the stencil and we fix it with Kapton tape to the workstation. We can use the stencil as in generic photo or one specially designed for Sony Vaio: stencil go6200 / go7600

reball bga sony acer asus toshiba

reball bga sony acer asus toshiba

Now it touches the ball of tin are used for this processor the ball size 0.6 …

reball bga sony acer asus toshiba

Finally we place in a painstaking processor on the motherboard, and we maintain a reflow at 200 ° for resolder …

reball bga sony acer asus toshiba

This is the tool I used in numerous repairs.

reball bga sony acer asus toshiba

After cooling down everything we can proceed to spread some thermal paste on 3 processors (little I recommend because if you overdo it you get the opposite effect to the heat conduction ..).

Then comes the other important operation to be carried out.

Muniamoci of a sheet of pure aluminum or copper with a thickness of at least a couple of millimeters and cut out 2 squares of 2x2cm.

These squares will be sandwiched between the processors and the heatsink.

This is the aluminum plate that I did give to a friend who works in the aviation industry …

Aluminum sheet thickness 2mm

This slab is actually little more than 2mm .. the problem for me was cut .. I used a pair of scissors from the workshop and then I proceeded to lay her going the plate making it flat.

In my case I proceeded to put two plates on two processors as in the picture, leaving out the CPU from the speech:

Nvidia GeForce GPU heatsink SONY VAIO PCG-7121M

second sink GPU Nvidia GeForce SONY VAIO PCG-7121M

On each plate I proceeded to smear another thin layer of thermal paste, then I screwed up the sink and reassembled everything.

Power-up, the first thing I did was check the temperature of the processor via one of the many small programs that run on Windows: I have found it to be at acceptable levels (approximately 50 degrees at power without doing anything). Then I reinstalled the graphics card driver that was immediately recognized as NVidia and not as ‘standard’.

Artefizi of even the shadow. Then always controlling the temperature I tested for the graphics card making her climb up to 99 degrees. No problem.

The result is that the Sony Vaio PCG-7121M is back to work without problems.

Sony Vaio PCG-7121M GPU with Nvidia GeForce

One Response

  1. John Holland 2 years ago

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