HD5850 vs HD7850

[Crazybob's Son]

Currently have a 5850 (as noted in another thread, broke a fin off the fan, haven't fixed the fan yet). Today I found a posting on craigslist for a 7850 at a price of $80. Would there be a drastic increase in credit? If so what kind of increase are we talking?

[Bryan]

IIRC the 7850 is NOT double precision ... the 79xx series is.

[John P. Myers]

The 7850 is double precision. Everything from the 7730 up has it. Problem is it's severely crippled. a 5850 has 4x the DP the 7850 has. The 5850 is also about 20% faster at SP.

The reason the 5850 is a better card than the 7850 is because things were numbered differently back then. Tier-wise, the 5850 is equivalent to a 7950; the 5870 to a 7970. Back then, the 5900 series was reserved for dual-GPU cards only - the 5970 being equivalent to a 7990.

[Crazybob's Son]

The 7850 is double precision. Everything from the 7730 up has it. Problem is it's severely crippled. a 5850 has 4x the DP the 7850 has. The 5850 is also about 20% faster at SP.

The reason the 5850 is a better card than the 7850 is because things were numbered differently back then. Tier-wise, the 5850 is equivalent to a 7950; the 5870 to a 7970. Back then, the 5900 series was reserved for dual-GPU cards only - the 5970 being equivalent to a 7990.

I see, so the 7850 will probably be better than the 4850 I have in another computer, but not the 5850. Just trying to see if it would be a drastic enough improvement for the $80.

[John P. Myers]

For projects requiring DP, the 4850 is still faster For SP though, the 7850 is 76% faster than the 4850.

[shiva]

man I had terrible luck with the 5870's I just broke them all the time. I think I have 5 or 6 of them laying around. maybe I should make sure they don't work.