Question Black screen with white non-blinking underscore

klack90

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Apr 23, 2019
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My firend have laptop Toshiba Satelite c855-1j7

CPU: Intel® Pentium® B950
Memory:4GB

When turned on it just show white non-blinking underscore and restarts, and that repeats that loop.
I can enter bios, i set USB to first boot device, but nothing happens.
I checked ram, chaned by slots it always diplay it, so that i assume is fine.
 
Dec 29, 2022
14
1
15
What OS are you running? Do you have a flashdrive laying around?

If you are running Windows 10/11, you can go to the official microsoft website and make a boot device with that flashdrive (must be at least 8gb) and plug it in. You can then go into BIOS and boot that USB. If that works, your copy of Windows might have been corrupted. There are options to try and fix your copy of windows using that USB.
 

klack90

Reputable
Apr 23, 2019
18
1
4,515
What OS are you running? Do you have a flashdrive laying around?

If you are running Windows 10/11, you can go to the official microsoft website and make a boot device with that flashdrive (must be at least 8gb) and plug it in. You can then go into BIOS and boot that USB. If that works, your copy of Windows might have been corrupted. There are options to try and fix your copy of windows using that USB.
Windows 7 is installed, and i tryed to boot from USB, still the same, nothing happend. I tryed bootable USB Win10 and Win7.
 

klack90

Reputable
Apr 23, 2019
18
1
4,515
Try booting the computer without the CMOS battery in there, perhaps the CMOS needs to be replaced? Also, it won't let you even boot into the USB drive if the HDD is unplugged?
finnaly progress, when i removed CMOS battery and HDD and usb, it all stays the same, and then i removed laptops battery and it let me boot normaly, strange but i cant believe that laptops dead battery causing this huge problem