I'm a realist. You're living in cloud cuckoo land if you think you can grab a 4090 for £600 this year.
Exactly this.. This is unlike GPU's before.. the 4090 was an odd one at release due to it being such a giant leap from the 3090 and now the 5090 benchmarks are out and it's only roughly a 30% uplift on average.
Generally the new 80 series would perform as well as or better than the previous 90 series, which the 4080 has done over the 3090Ti by about 25%... but from everything we have seen, read and can determine just by looking at cuda cores etc the new 80 card is only going to be about 10% at best than the 4080 Super...
Also both the 40 series and 50 series have Frame gen... the only difference is that one can do 2x and the other can do 4x. then we have the VRAM which the 5080 only has 16GB.. if they had put the same amount as the 4090 then this would have instantly devalued the 4090 more.. even if the 5080 had worse performance than the 4090 but had the same amount of VRAM.
No matter how you look at it the 4090 is the 2nd best card on the market right now and plenty out there still have years of warranty... mine still has about 18 months and i got mine on release, which from reading, most AIB's warranty the card, not the purchaser, so it automatically transfers.
Now would i personally spend £1000+ on a used GPU probably not, but all you have to do is look at the auction websites etc and see that there are plenty that will and yes there might be a bit of a bubble at the moment but it's easily readable that the 4090's value will stay high.
This will remain until they inevtiabley bring out a 5080Ti/Super and the VRAM and performance either match or perform better than the 4090.