Aspire 7750G - black screen until windows7 starts - no vga signal

mrmysterious

Hello community,

I use an acer aspire 7750G model which I bought back in 2013. It runs actually win 7 ultimate edition which i want to replace with win 10 (i have that on dvd). Now I wanted to boot from cd drive and change boot priority in the bios. That is where the big problem begins: On pressing F2 at start (and repeatedly afterwards) no bios appears. The screen remains black but I am sure the bios is present, although I just cannot see it. That is because the booting is interrupted when pressing F2, as if the bios is present. I can ecape this with esc and enter or f10 and enter so win 7 can start. So nothing can be seen until the windows drivers activate the radeon 6850M graphics device.

What i did to solve the problem:

I testet the vga port with an external monitor plugged in - there is a "black" vga signal present, means the screen shows it is receiving an analog signal but nothing can be seen.

I tested the keyboard input with an external keyboard - nothing changed

I tried to reset the bios (assuming there is an option to enable/disable an onboard vga device - to default settings) removing the cmos battery for a long period of time - nothing changes.

I tried to reset the bios to defaults connecting the hardware gaps on the board (jumpers) -

nothing changes.

I flashed the current bios v.1.21 with the older 1.17 - nothing changes.

I updated and re installed all relevant drivers for graphics device as well as for the chipset and bus. Nothing changes.

No I think there might be a hardware fault. The onboard vga device does give out a signal without any brightness. But I do not even know if an onboard vga device exists or if this is part of the Radeon HD 6850M graphic card soldered onto the mainboard.

So I thought of bypassing the problem because all I want is to (one time) change boot priority in order to be able to install win 10.

I can only think of operating the bios (which I asume present) blindly but I do not know

1. in which tab it starts and
2. which options are currently listed,
3. which arrows to press to go to the right menu and so on.

So I would badly need someone with the same model to guide me through the InsydeH20 setup so I can change the boot menu OR if existed activate the internal vga (if not defective)…

Greetings

MrM.

StevenGen

https://community.acer.com/en/discussion/692876/aspire-7750g-black-screen-until-windows7-starts-no-vga-signal

Try pressing Ctrl+Alt+Del that will first pause the startup process and allow you to then press the F2 key to access the bios.

If the above doesn't work then try these steps, to access the BIOS on your Acer Aspire 7750G:

1. Power off your laptop.
2. Power on your laptop and immediately start tapping the F2 key repeatedly until you see the Acer logo.
3. If that doesn’t work, try holding down the Power button until the laptop shuts down completely, then power it on again and quickly tap the F2 key a few times 1.
4. If you’re still unable to access the BIOS, try resetting it to its default settings by following these steps:

Press and hold the Power button for 10 seconds or until your system shuts down completely.

Power on your system and immediately press F2 for notebooks or Delete for desktops to enter the BIOS

Press F9 and then Enter to load the default configuration.

Press F10 and then Enter to save and exit 2.

If all the above steps don't work and as a last resort, but be careful as downgrading bios can brick your laptops bios and I take no responsibility for either the bios version 1.15 authenticity or how a downgrade will work!

Try this bios downgrade as a last resort, see the bios drivers for the Aspire 7750Gs from HelpDriver and downgrade to bios Version: 1.15 - Titled: 1. Adds Chicony camera ID. 2. Fixes CMOS screen sometimes have extra underline. 3. Adds NVidia N13MGE3 and N13PGL2 VGA. 4. Updates Microcode v0000001B for 206A7. 5. Adds dGPU AMD Seymour XTX & Thames XT - and see if this bios brings the screen back as this bios is specifically related to the CMOS and gpu. Good luck and hope this helps you out.

mrmysterious

hi there,

thanks for answering on that topic. I have just tried all of that. At last I have downloaded the Bios Flash 1.15 from the recommended source but the flashing failed with the message ""Open flash.sys Fail".

I am running win7 on 64bit. That might be the problem. Those old versions don't support that, do they? I tried others too, just the same. I was able to upgrade from 1.17 to 1.21 (which was running before I downgraded to 1.17). Besides that I do not understand the filesize which is given as 5.3 MB, but the file (extracted) is only at 1.14 MB on my hd.

Anyways, I do not think the bios is the problem…as i assume it present and I enter it with F2 already. It is just not visible due to some black screen (which corresponds with no vga signal present (or let us say a "black" vga as an external screen detects an analog signal present - though it's screen remains black too)

So unfortunately no solution so far but thanks anyway.

greetings

MrM.