CLEVO P150SM-A won't still post after changing gpu

Recently, my old laptop died and did not post and I posted here before. ( http://forum.notebookreview.com/threads/clevo-p150-sm-a-sager-np8268-not-posting.832598/)., I now got a hand of a new GPU (GTX 970m bought from aliexpress, with good reviews and clevo compatibility) and tried booting it up after installing it. Apparently the laptop still did not post but turns on with black screen but no backlight. I tried different ram sticks as well and tested it in a different laptop and they weren't the problem. The laptop power indicator turns on, and if i remove the gpu, the 3 lights beside the power blinks. FN+1 still works and if I leave the laptop on for a while, the cpu fan turns on. I'm starting to think it is a problem relating to display? does anyone know if clevo laptops can still turn on even if theres no internal display detected? cuz it couldnt have been the mobo or the cpu since, firstly the mobo still detects if theres a gpu or not, secondly it couldnt been a cpu problem since the fans turns on when it reaches a specific temp? I'm not really sure if what i think is right.

 

Display is optional for booting.

GPU = no boot
no GPU = additional indicators for being powered on

As to the GPU / no GPU issue it seems like there might be a bad connection on the board/s causing the display not to work. The "internal" display might have a loose connector on either end of the cable or it's more of a HW issue with the board itself. W/O the ability to swap chassis' for components it's a difficult to figure out situation unless you're going to trace things out with a multimeter to find the fault.

The principal duties of the main BIOS during POST are as follows:

• verify CPU registers
• verify the integrity of the BIOS code itself
• verify some basic components like DMA, timer, interrupt controller
• initialize, size, and verify system main memory
• initialize BIOS
• pass control to other specialized extension BIOSes (if installed)
• identify, organize, and select which devices are available for booting

The functions above are served by the POST in all BIOS versions back to the very first. In later BIOS versions, POST will also:

• initialize chipset
• discover, initialize, and catalog all system buses and devices
• provide a user interface for system's configuration
• construct whatever system environment is required by the target operating system

So, you didn't report any BEEPS which would indicate you're getting beyond these checks. Notice none of them are looking foe a GPU / Display.

The mention of no backlight with/w/o GPU seems more electrical as even w/ a black screen if there's power being provided it should "glow" a bit. The issue of neither internal/external display not working leads back to signaling / electrical on the board not passing the signal to the ports.

 

Thanks for replying, sorry for the late reply, was out the whole month and just got back now.
So what you are saying it could be a problem in the board it self not giving power to gpu/display? Is it possible to still have this repaired or do I have to replace the mobo already?
If I were to replace the mobo, it would take me another 200$, with that I think it is more worth to sell the mxm cards I have (870m/970m) right?

 

It depends on where the fault lies. If you're good with a meter / solder you might be able to pin down the issue for very little $. If you need it up and running again sooner then a board swap is more efficient.

It also comes down to $ if you want to sink more into it before replacing it. It's a bit of a balancing act as to when to throw in the towel and just swap it. Another issue is can you get your hands on a replacement board?

 

Oh i can probably do with a meter and some soldering if there are given resources on how to do it, do you have any references that I can look up to get that started?

I do have acces also in buying a board (from aliexpress) but it would cost me another 200$ which i think its prolly is the last option if ever I really want to revive this laptop.

 

I don't have anything specific for doing this.