GPU cant be detected

After all that troubleshooting, I would recommend to replace the card. 

im still covered by warranty will dell replace this card??

Yes definitely.

i ran hwinfo and noticed that gtx 770m features bus mastering is disabled and fast back to back transfer is not capable while intel hd is opposite

Hi!

The Video Card seems to be disabled. Since you mentioned is not detected in the BIOS either, just in case, try using the function key (FN+F5) for Switchable Graphics and restart the computer.

If the nVidia card shows on the Device Manager but not on the BIOS, follow the steps on this article.

Let me know if the Video Card shows up on the Device Manager or BIOS after that. 

Hi naomi!

My video card is detected by the bios. If i switch graphics nvidia is still not working it is detected on the device manager but windows says that this device is stop because it has reported problems. This problem started when nvidia updated my laptop to 332.21 i will be trymg that article 

hi nami! 

when i try to click the article link it just leads me to dell official site not the troubleshooting guide :(

Sorry, the link to the troubleshooting article is fixed now, you can try it again here.

It seems I misunderstood you. So if you're getting that error, try system restore and use a restore point before the 332.21 driver was installed. 

If the problem persists after that, please send an email to AWSocialMedia@dell.com with your service tag and a detailed description of the problem.

I have tried that solution but it didn't fix the problem. I can't use system restore because Ihave formatted my laptop and edited the partition. But the bios can detect my nvidia and also the device manager however I can't use nvidia i think windows disabled it 

Since you mentioned you already tried re-installing drivers and OS, the problem seems to be hardware. Send us your information so we can review your case further.