Can't boot into anything!?

[SgtStiffler]

So I flashed my BIOS to the latest version.
I can't boot into anything now. My OS won't boot, I can't use the disk to recover it because it won't boot. I have tried restarting the CMOS, I've tried setting fail-safe defaults. I've tried all of the HDD settings such as ACHI etc. Please help me, I'm stuck!!
Edit: I can see the USB/CD, it just doesn't boot. It normally just restarts the PC.

 

[cars12345]

First, unplug any non-boot drives, and check boot sequence. Then try to boot.

What motherboard is it?

 

[SgtStiffler]

First, unplug any non-boot drives, and check boot sequence. Then try to boot.

What motherboard is it?

Thanks for the reply,
I've tried these things already. It's an MSI motherboard, I'm not too sure on the exact model. I have tried a few USBs and a CD. None seem to work.

 

[cars12345]

First, unplug any non-boot drives, and check boot sequence. Then try to boot.

What motherboard is it?

Thanks for the reply,
I've tried these things already. It's an MSI motherboard, I'm not too sure on the exact model. I have tried a few USBs and a CD. None seem to work.

I am assuming the psu works, and so does the cpu fan. And your are also able to get into the BIOS?
Are you going in a cycle of failed boots?

 

[SgtStiffler]

First, unplug any non-boot drives, and check boot sequence. Then try to boot.

What motherboard is it?

Thanks for the reply,
I've tried these things already. It's an MSI motherboard, I'm not too sure on the exact model. I have tried a few USBs and a CD. None seem to work.

I am assuming the psu works, and so does the cpu fan. And your are also able to get into the BIOS?
Are you going in a cycle of failed boots?

Yes, the PSU and CPU seem to be working OK. I've also tried two GPUs. I can go into the BIOS, yes. I can't boot off a bootable USB/CD, therefore I can't fix or install an OS.