ASUS K72JR artefact on video

[jasko_jacker]

I have substitute the old gpu chip with a new chip (same part number) because the video showed artefacts but the situation don't change. Is possible a vram issue ? or a corrupt bios ? thanks
News:
I have placed the heatsink (only cpu) and the video is ok, it is possible that a partial cpu socket desolder can cause this problem?

[dj_ricoh]

Re: ASUS K72JR artefact on video

no!
i got a asus G1S did a reflow and because i was so paranoia i saw a vram with thermal pads; i replace the original and place 2x pads and after a hour it made artifacts.

i know its from that vram because the keyboard was a little bended (saw after artifacts came)

if its bad and does not revive from a reflow i think i have to change the ram.

p.s. everything works movies games gpu normal detect everything; OFC with artifacts

[highpulse]

Re: ASUS K72JR artefact on video

its VRAM issue , specially if the vram have the red glue , you must remove the old vram and replace new vrams (they're cheap)

[jasko_jacker]

Re: ASUS K72JR artefact on video

I confirm that an vram issue, I remove all vram chip but i haven't the samsung part but only Hynix.
I read on schematic: 0000 for samsung and 0001 for hynix but without serigraphy I have a problem to identify the pads. The vram I removed are samsung and I should see four pads not connected to ground ?
I attach the mobo pics and a part of schematic named asus k72jr

[Th3_uN1Qu3]

Re: ASUS K72JR artefact on video

It is common practice to put "no connect" pads to ground. Don't worry. Just change the strap as per the schematic for your Hynix RAM and it will work fine.

[jasko_jacker]

Re: ASUS K72JR artefact on video

Ok, Now I see the right schematic vram strap.
thanks

[jasko_jacker]

Re: ASUS K72JR artefact on video

I have a bad idea to change the samsung vram with hynix but I't very difficult to find the strap without serigrapy, If I power the board to find the volt ref to identify the strap can I damage the hynix vram ?

[Th3_uN1Qu3]

Re: ASUS K72JR artefact on video

No. The strap likely controls some timings - it is likely that the picture shown will be distorted, but the RAM is very unlikely to be damaged by a timingset.

[jasko_jacker]

Re: ASUS K72JR artefact on video

Finally I found it without powered the board, with a multimeter and after desolder the 0 hom res that is the switch from +3VSG (for m92) and +1.8SVG for PARK XT
I post the pic for future use

[Th3_uN1Qu3]

Re: ASUS K72JR artefact on video

And the result? Does the laptop work well now?

[jasko_jacker]

Re: ASUS K72JR artefact on video

Work fine

[Th3_uN1Qu3]

Re: ASUS K72JR artefact on video

Good job. It's always a good feeling when such an involved and time-consuming repair is successful.