Which GPU to buy?

Are you even able to buy gpu's now with the shortage?

Are you a millionaire? I do not recommend buying a GPU now. Wait at least a couple of months, it looks like the era of Ethereum mining is coming to an end - read Ethereum 2.0 on the Internet - soon video cards on the secondary market should be very much cheaper.

You buy what your budget allows you to. Can't exactly tell you what to buy if you don't specify anything, but go with a 3080ti I guess?

Maybe you should try to buy GTX 1080 or something. Cheap and not bad.

recently bougth a GTX1660 AND im really happy with it

my own suggestion is rtx 3060. but when there is stock

If you are looking to spend 400-600$ get a 3060/3060 ti if you manage to find any at MSRP lol (probably wont be available anywhere at msrp tho which is why i wrote 400-600$). If you have a bigger budget, see if you can find a 3070 anywhere.

Nothing really wrong with AMD really. I currently have a Sapphire RX 5700 XT Nitro+ no issues at all. I'm going to give it to my cousin once I can get the RX 6700 XT Nitro+. I can't trust Nivida after I had 3 660ti GPUs going out on me. After that I went with an MSI R9 290 and haven't left AMD since.

if u want cheap then dont get nvidia stick to something like radeon

Now it is not good time to buy GPU ;(