Of course they all had similar performance because for the most part they were the same card
The 285 was a rebranded 280 with a higher clock and slightly faster memory and so on. That's pretty much what Nvidia have done for years.. Here are the ones they have been publically flogged for that I have read about..
9800GT - 8800GT with a faster clock and a couple of other minor tweeks. Same exact main GPU, though.
9800GTX - pretty much a slightly higher clocked 8800GTX with some more pipeplines (that were there all along). Slightly faster ram, too.
250GTS - basically a 9800GTX.
9600GT - see 9800GT. This one was a rebranded diddled with 8600GT.
240GTS - rebranded 9600GT or was it 9800GT with some more pipelines.
Repeat ad nauseum. As I say, I know people who binned their 8800GTXes to buy a 9800GTX. Imagine their surprise when they ran 3DMV and only got about a 10% speed increase? Or imagine how gutted they were when it finally came out that they had basically paid a premium to buy back the same card they had just pulled out?
The 8800GTX was an absolute revelation from Nvidia, it really was. It came as a shock out of nowhere and gave ATI a seriously concussive slap. ATI were playing catchup right up until the 4xxx IMO, but even that didn't shame up the 8800GTX and it took them about two years.
Since then though? it's been ATI all the way. The 4890 traded serious blows with the 280/285 and cost a good £150 less. Infact within a couple of months the 4890 could be had for about £170, half of what Nvidia wanted for the 285.
The crazy part of all of this? Go to Ebay and punch in 8800GTX. Look how many you will find that are listed as faulty.
They need to do something about the temps and they need to do it fast. I
truly hope they may get a fingernail into the ladder with the 460 as it could seriously be one of the last throws of the dice for them. On the surface? It's business as usual but in the real world they are facing some serious financial problems. The very fact they ended manufacturing of the 200 series GPUs
four months before they got Fermi out the door is a dire situation indeed. I mean, I know they are big, rich and powerful but NO COMPANY can afford to rest on its laurels for four months and sell nothing.
And the cost of Fermi? Jesus, let's not even go there on that one.