Graphics stopped working on my Acer 7720ZG with nVidia GeForce 8400M GS

I have an Acer Aspire 7720ZG (Acer product number LX.ANJ0X.009) which has nVidia GeForce 8400M GS with 256 MB on-board RAM. It has worked well for years, except now the display does not work any more. I expect that the problem was caused by overheating, the laptop had sucked a lot of dust inside. The failure occurred suddently and there were no software or configuration changes near that moment, so I think this is a hardware problem.

I replaced the graphics card (Acer product number VG.8MG02.001), but it did not help much. Occasionally when I boot I see a valid screen for a second or two, but most of the time the LCD back light is on but the screen is black. When I connect an external monitor, it displays stripes but not the first boot messages, which are in normal text.

However, I can boot the machine blindly into Linux and I can log into it via the network. Everything else seems to work except the display.

Does anybody have a suggestion on what kind of a hardware failure I have?

Linux dmesg shows the following messages:

Code:

$ dmesg | grep -i nv
[   14.520228] nvidia: module license 'NVIDIA' taints kernel.
[   16.412090] nvidia 0000:01:00.0: power state changed by ACPI to D0
[   16.412107] nvidia 0000:01:00.0: power state changed by ACPI to D0
[   16.412126] nvidia 0000:01:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
[   16.412143] nvidia 0000:01:00.0: setting latency timer to 64
[   16.412391] NVRM: loading NVIDIA UNIX x86 Kernel Module  280.13  Wed Jul 27 16:55:43 PDT 2011
[   42.599451] NVRM: RmInitAdapter failed! (0x26:0xffffffff:1077)
[   42.599469] NVRM: rm_init_adapter(0) failed
[   43.203341] NVRM: RmInitAdapter failed! (0x26:0xffffffff:1077)
[   43.203359] NVRM: rm_init_adapter(0) failed

Additional information:

Code:

# cat /proc/driver/nvidia/gpus/0/information 
Model:           GeForce 8400M GS
IRQ:             16
Video BIOS:      ??.??.??.??.??
Card Type:       PCI-E
DMA Size:        40 bits
DMA Mask:        0xffffffffff
Bus Location:    0000:01.00.0
# cat /proc/driver/nvidia/version 
NVRM version: NVIDIA UNIX x86 Kernel Module  280.13  Wed Jul 27 16:55:43 PDT 2011
GCC version:  gcc version 4.6.0 20110603 (Red Hat 4.6.0-10) (GCC)

 

My guess is that it's failing/failed. The 8400m is one of the Nvidia cards made with faulty solder.

Have you tried connecting it to an external screen?

 

Yes. It displayed only stripes and other strange things, but not text nor graphics. For a second it displayed a fraction of the boot messages (in text mode) but it turned into stripes again quickly.

Occasionally the display (LCD) works. Today it worked once almost for a minute! I was able to log in via the graphical screen, but within a minute the machine locked up and I had to boot it by pressing the power button down for a while.

Do you think that the problems is in the card itself or in the motherboard (or somewhere else)?

 

From your description of when it's plugged into a monitor, my money's on a bad video card.

 

Try replacing with a different card (e.g. a Radeon or a 9000-series Geforce). The 8400M GS is the single most Bumpgate-affected card; it's easily possible that even a new one will be dead out of the box.

A word of caution, though: the 9500M GS is really a rebranded & slightly overclocked 8600M GT, so it is prone to failure the same way as any other 8xxx-series GeForce.

 

I have ordered yet another video card VG.82M06.001 (ATI Radeon 3470 256MB MXM II display card for Acer laptop) in order to test this. It will take some time before I get it.

However, I have continued tests with the new nVidia card. It seems to work for about one minute at first boot, if I don't use the computer overnight. Or if I cool the machine outside at about 10 degrees centigrade for 30 minutes, it will work for about one minute. After one minute the screen stops working, but otherwise the machine works: I can blindly log into Linux (the machine has dual boot Linux and Windows Vista) and enable networking and then I can log into it via the network, and it will work for at least two hours.

When I installed the new video card, I removed old thermal paste and added new one. I bought the new thermal paste from an electronics store. The type of the paste is ELECTROLUB HTC NON-SILICONE HEAT TRANSFER COMPOUND, CODE: EHTC02S.

 

The new card is broken out-of-the-box, presumably due to Bumpgate. Due to the different thermal expansion coefficients of the die, the substrate and the bumps, a critical bump does make contact when the chip is cooled down, but once temperature hits a level, it loses contact. A reflow may help, though only temporarily, as it does not replace the low-quality bump material inside the chip.

 

Im about to order a new ATI Mobility Radeon 3470 256MB MXM II card just like you, but this is for my 5720G acer laptop, any chances of incompatibility?
Sorry about my english and thanks.

 

The 7720G is just a 5720G in a bigger case. "Z" simply means that the machine originally shipped with a dumbed-down CPU & weaker WiFi, compared to the non-Z version (the only exception is the 5738Z, which is totally different from any other model with 5738 in its name, and is really a rebranded Emachines).

 

So, I can assume that this card will work fine on my laptop? someone has put before this card on a 7720G?

Thanks a lot!

Edit:
Ok, I found this: http://forum.notebookreview.com/6994562-post1195.html great help .net, thanks!

 

The card was broken. The seller replaced the card and now it works!

 

HD3470 isn't working fine with my Aspire 5720G, i only get a black screen, no beeps, no other problems, windows boots normally and sounds are working but i can't see the Acer logo, and of course I can't see my desktop. I can only see what's happening through remote desktop with my iphone, I tried installing the ATI drivers but nothing happened... The card's name on the resolution menu is "RDPDD chained DD" is this normal? What can I do? Im running Win7x64 and the laptop boots normally with his GeForce 8400m gs, but with artifacts and sometimes crashes... That's why I'm trying to replace the old card.

Please help... Thanks and sorry for my english.

Edit: I have update my laptop bios to 1.42 (high available) and still no results, seems that the card is incompatible with Aspire 5720G or broken.

 

@rbrt: The latest official BIOS is 1.45, though some old Acer sites do not have that one. A version modded for better MXM compatibility is available in this forum, in the x920G thread.

However, ATI cards usually don't read the MXM structure, but rather use hardcoded output device configuration, so your best bet is finding another VBIOS.

 

I have already ordered a new card, this time a 9300M GS, I'm prying this time for no problems... What do you think?

 

The 9300M GS should be OK (it is basically unaffected by Bumpgate), but rather weak - in fact, it has less SPs than the 8400M GS. It is about on par with the 8400M G. (Oddly enough, the 9300M G is a rebranded 8400M GS.)

 

I didn't see the 9300M GS on the compatibility list, but works great on 5720G, here a capture:
View image: gpuz