No BIOS Prompt Black Screen With flashing cursor

Esdisaster

Reputable
Feb 10, 2016
2
0
4,510
Hello, my dads system has recently started having intermittent boot problems.
It seems to have a 50/50 chance of booting up successfully into windows.

On boot the Bios splash screen fails to show and goes directly to a black screen with a flashing cursor/prompt. No beeps when it fails. Single beep when it boots. I have some basic IT knowledge but something such as this feels a bit beyond my knowledge. I am inclined to think that since the splash screen does not show it must be a hardware related problem with the motherboard, but I am not 100% sure that this is the correct diagnosis.

Recent Changes:
introduction to internet access via Laptone Wireless Internet USB Adaptor WiFi Dongle 300Mbps
The machine has been working successfully for the past year offline. there seem to be issues when connecting this device, as direct and indirect connection to the rear usb ports fail to access the dongle correctly after it is recognised by windows as being connected. this device seems to work via a usb multi socket extension connected to the front usb hub.

Could the wireless dongle have had any effect related to the booting of the system on its own or perhaps just unstabilized an old system with outdated drivers? Or is it more likely that the hardware is in fact failing and these symptoms are unrelated.

It's a 4 year old machine custom build, with a new 500w semi modular power supply with sufficient cooling and stable temps.

OS: Windows 7
MB: ASUS m3n78 pro
CPU: AMD Athlon x2 7750 Black Edition
GPU: Saphire Radeon 4870
DDR2: Corsair Vengance 2x2gb
HDD: Seagate 250gb Internal SATA

I really appreciate any advice offered.
Thanks for your time.
 

Barty1884

Retired Moderator
Have you tried to boot without the USB dongle attached? It sounds like a boot priority issue and, if you have "USB" set to the boot Priority #1, it's likely confused (for lack of a better word) as there's no bootable USB.

Remove the USB dongle, see if it POSTs. If so, go into BIOS and look for "Boot Priority", "Boot Order" or "Boot" menu and ensure your HDD/SSD with OS is set as Boot Priority #1. Then reboot, attach the wifi dongle & see how it reacts.
 

Esdisaster

Reputable
Feb 10, 2016
2
0
4,510


Hi, thanks for the speedy reply.
I have now checked the boot priority and HDD is set to #1(only 1 HDD in the system), CD ROM is set to #2 and no USB/Flash devices are assigned a priority.

All Peripheral Devices and CD's have been removed with the exception of mouse and keyboard and unfortunately the system still intermittently fails to boot without sign of the normal BIOS splash screen nor allows any attempt to access it via the DEL Key, F2 or F8 Keys. During this state all fans are functioning, CD Drive has power and can be opened or closed. No Beeps received during a Failure to Boot.

Could something like this be caused by power related issues?

Thanks again for your response.