Re: hp 840 g4 need help with system hardware configuration

OK so lets look at this another way then. What if we needed to replace the mainboard for an 840 G4 touch? How would we know if that additional hardware for touchscreen is present if HP only sells one replacement board?

In the service manual there is mention of an LCD cable kit. It does not specify which screen it applies to so I think it may come with cables that cover all possible screen configurations. It's about 20usd so I think I will order it and see if there is anything included with it that differs...

Re: hp 840 g4 need help with system hardware configuration

Here's something interesting I found when doing some more digging.

The mainboard info on my machine is missing when I look at system information. The first screenshot is my actual PC, note the mainboard info is not present. The second screenshot was borrowed from an ebay seller selling a 840 G4 touch, their mainboard info is populated. Could this be a problem or part of my solution?...

Re: hp 840 g4 need help with system hardware configuration

I've been unable to find a schematic for this board unfortunately. The HP part number is
917503-001.

This page contains a cross reference of machines the board is installed in if you click towards the bottom of the page
[URL="http://partsurfer.hp.com/Search.aspx?searchText=917503-001"]http://partsurfer.hp.com/Search.aspx?searchText=917503-001[/URL]

Some of those machines are touchscreen models.Re: hp 840 g4 need help with system hardware configuration

Hey guys I need some direction here, a recent upgrade is not going as smoothly as planned. So I got an 840 g4. It shipped with a matte HD panel that looked like trash. I replaced it with a complete glossy HD display assembly that is also a touchscreen. The new display assembly has an additional connector on the display cable, this connector mates to a previously unused female connector on my motherboard. The cable says something about LCD touch so I am thinking it's the correct cabling for touchscreen to my main board.

After connecting the new display the picture works perfectly...

Re: New Members - please post your introductions here

Hi I'm mark and I am here because I'm having some issues with a particularly difficult laptop. Seems like I might be in the right place.