HD4850 no signal to monitor

[giorgossidir7]

System:
Processor:Amd Athlon x2 4200+
Ram:2gb ddr2
Gpu:Asus radeon hd 4850
Hdd:500gb seagate sata
Motherboard:unknown
Motherboard graphics:Nvidia geforce nforce 6150se
psu:400w

Everything is working right besides the fact that when i connect the gpu to the monitor we get no signal.The gpu is recognised on device manager,its fan is spinning and it produces heat so i believe that the gpu is not the problem.It is connected to a monitor with a dvi to vga adaptor which is working because we tested it on another computer.When i connect it to the integrated graphics it works perfectly fine.Also the psu did not have an 6pin so we bought an adaptor and connected it to the psu.The computer was built to play older offline games.What should i do?

 

[cin19]

System:
Processor:Amd Athlon x2 4200+
Ram:2gb ddr2
Gpu:Asus radeon hd 4850
Hdd:500gb seagate sata
Motherboard:unknown
Motherboard graphics:Nvidia geforce nforce 6150se
psu:400w

You need other PSU, because 400W is not enough to power up the hd 4850.

 

[giorgossidir7]

I tried connecting another gpu but it got recognised as unknown vga device and we still had no display from it

 

[cin19]

Try go into the BIOS to disable the onboard igpu. Then reboot the PC to see you can use the PC or not.

 

[giorgossidir7]

Already did that but it didn't work

 

[cin19]

So that MB has the compatibility problem, usually you can update the BIOS to solve that problem, but you said the MB brand is the unknown, I think you may or may not find the BIOS. Also I know the nvidia chipset MB usually has that kind the compatibility problem.

 

[giorgossidir7]

I will search tomorrow for the motherboard model and I'll update.Anyway,how to update your BIOS?