Hp Touchsmart IQ770 Desktop, Black Screen [ Edited ]

[Octavean]

For what its worth I have an out of warranty HP Touchsmart IQ504 with what seems like a blank screen issue as described here. The screen remains blank, but the touch screen seems active and will beep when touched. I think the system will beep once when booting which is normal when the BIOS screen is displayed under normal conditions.

Anyway, like others here, I’m not at all happy about this and have little recourse. I will attempt to get an estimate at least. My guess is that its either the graphics subsystem or the screen itself but there possibly may be a power issue.

Anyway, if you look at the motherboard for the IQ504 (AKA the IMISR-CF (EVE), which probably isn’t much different from the IQ770 motherboard (save for chipset and CPU) you’ll notice two ports at the top:

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01489642&cc=us&dlc=en&lc=en&jumpid=reg_R1002_US...

I think they are labeled SLVA (1 and 2) or SVLA (1 and 2) or something like that. I believe these to be the video outputs but I could be wrong. Only one seems to be used on my system which uses onboard video via the Intel Mobile GM965 Express chipset. Anyway, there is a MXM slot at the top right of the board which in my case is empty.

Anyway, if I had proper documentation for the motherboard it would be easier but my guess is that one would install the MXM video card (9300M or 9600M-GS) along with the cooler fan assembly and then switch the video lead from the first to the second!?! Not really sure but I don’t think there is a physical cable that goes from the MXM card to the motherboard so it makes sense to me that you would simply switch from lead 1 to lead 2.

The idea here being that if the integrated video wont function correctly then maybe an added MXM card would? Conversely, the IQ770 seems to come with the MXM video subsystem but may also have integrated video on the motherboard via the gForce 6100 chipset (most if not all such motherboards do):

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00858789&tmp_task=prodinfoCategory&lc=en&dlc=en...

Therefore, removing the MXM card and reassigning the video cable might do the trick. Or maybe just switching the video lead from 2 to 1 would work without removing the MXM card.

Naturally you’re mileage may vary and I’m not responsible for any damage to your (already inoperable) system if you try this.

[Hiddenvision]

If the Video card has gone ( comman fault) then just remove it and switch the video cable to the other port. I described it fully in another simular post.

[pies666]

Unfortunately, it doesnt work for me. No matter if lcd cable is connected to slva 1 or 2 still black screen (everything else work fine)... Did you switched any jumper or just this 30pin cable from slva 1 to 2?

I wonder if my nf-g6100 north brigde is ok if there is no screen even in slva 2 :/

[Octavean]

Perhaps resetting the BIOS would help after switching the cable. Removing the CMOS battery might do that or you could probably do it blindly with the right set of key inputs. Did you actually remove the MXM card though?

[Hiddenvision]

I have another machine (772) that the onboard video has lost the plot.

Applying a small amount of pressure around the chip will sometimes allow full boot.

If this is your problem then the mother board needs to be reflowed around the onboard graphics chip.

It is a shame that HP do not release some propper tech notes on products that are known to fail but not covered under warrenty..

[Hiddenvision]

Sorry Octav. I missed the last part of the question.

Yes I had the card rght out, with it in the grapics was still corrupt even after changing cable positions.

I have since replaced the card with another and the machine is back up to full spec, although I can't tell the difference.

Hv. 

[Hiddenvision]

No Bios reseting was required,

it was simply a matter of removing the faulty card and relocating the cable.

Once windows loads it will discover the onboard graphics and load the required drivers.

Hv.

[hp-notinmyhouse]

Black screen here too, is there a fix for this ?

[Hiddenvision]

If non of the main components on the board have fried then removing the graphics card may help.

I describe the process in another post I wrote.

[Octavean]

I still haven’t fixed the problem with my inoperable HP Touchsmart IQ504. However, this was part of the documentation that helped me to develop the thought process in correcting it:

HP TouchSmart IQ500 series PC Product End-of-Life Disassembly instructions (4136.6KB, PDF)

http://www.hp.com/hpinfo/globalcitizenship/environment/productdata/Countries/_MultiCountry/disassemb...

If you look at page 29 (29/66) you’ll see a photo of the upper left side of the IMISR-CF (EVE)
 Motherboard along with its CPU and MXM GPU cooling assembles respectively. Heat pipes lead to the CPU and MXM GPU. Under the MXM GPU cooler fan you’ll see from left to right the LVDS1 (open) and LVDS2 (used) ports.  My particular model doesn’t have an MXM card although it does have a fan in this position minus the heat pipe leading to nonexistent MXM card. My guess is this serves as a case fan. However, as stated before, the LVDS1 port is in use with the onboard video not LVDS2 as shown in the picture with MXM video.

In my case switching to LVDS2 wouldn’t likely accomplish anything since there is no MXM card installed and I don’t want to spend money on one unless I know it would correct the problem.

My plan was to use a laptop to attempt to output to the Touchsmart screen to make sure the screen and the screen transformer were fully functional but the pin out on the laptop was slightly different.

Right now I suspect the motherboard / motherboard integrated video in part because the system seems to turn itself off and then back on when you hit the power button. A defect in the screen or transformer shouldn’t cause that type of glitch. 

I have come across a few replacement motherboards but not at prices I care to pay,…well with the exception of e-bay.