Single overclocked Ati X1800XT beats 2 7800GTX in SLI

[Metalmurphy]

Aperently some finnish guy was able to overclock the new Ati X1800XT to beat 2 7800GTX in SLI (not overclocked obviously) in 3Dmark :o The new R520 chip really seems to win alot of points concerning overclocking.

Source: http://www.theinquirer.net/?article=26818

I sure was surprised when i read this oO

[GCFreak]

Goodness. ATi have done it this time :)

[shinmajin]

id like to see what you could do with them if you put them in crossfire

[ChankastRules]

Yeah, when( if )ever that'll be avaliable :D

[cooliscool]

It amazes me how any sort of core optimization could make any 16-pipe chip outperform a 24-pipe chip. ATi definitely suprised me with R520.

[D.D.]

Yeah, when( if )ever that'll be avaliable

wat will be, the x800xt or xfire ? :D

[ChankastRules]

wat will be, the x800xt or xfire ?

The combination of x1800xt and xfire :P

[Master Chief]

Well AMD is coming out with a new socket. I wouldn't be suprised to see a PCI Express x32 port on these new mobos. Also, I think NVIDIA is waiting for something before they release their next card. My guess is they are just gonna keep going back and forth with ATI...

[fivefeet8]

It amazes me how any sort of core optimization could make any 16-pipe chip outperform a 24-pipe chip. ATi definitely suprised me with R520.

The 625mhz core and 10 gigabytes of extra memory bandwidth helps a lot. ;) It's not suprising at all to me. 3dmark '05 is very vertex shader dependant. Ati's cards have always had more vertex shader performance and the R520 is no different.

[cooliscool]

Regardless, a 16-pipe chip at 625MHz has less fillrate than a 24-pipe chip at 450MHz.

Memory bandwidth is also nothing when bottlenecked by low fillrate. ;)

[fivefeet8]

Regardless, a 16-pipe chip at 625MHz has less fillrate than a 24-pipe chip at 450MHz.

Memory bandwidth is also nothing when bottlenecked by low fillrate. ;)

Actually, the G70 has only 16 ROPS and the standard core clock is 430mhz. So the fillrate theoretical limits are:

G70
430 mhz x 16 ROPS = 6,880 mpixels/sec
430 mhz x 24 pipes = 10,320 mtexels/sec

R520
625 mhz x 16 ROPS = 10,000 mpixels/sec
625 mhz x 16 pipes = 10,000 mtexels/sec

I doesn't quite have that much of a fillrate dis-advantage at all really. But with it's 625 mhz core clock which means that it's vertex shaders are also clocked at 625 compared to the 470 mhz vertex shader independant clock on the G70. Vertex Shader performance makes much more of an impact in 3dmark2k5 than in most if not all games out right now. Most of which are more prone to Pixel Shader performance.