HD 4890 vs GTX 275 – Specs Leaked

[Apokalipse]

Except that ddr5 is NOT more than double the speed.

It's double the speed of GDDR3 at the same base frequency on the same bus width.
GDDR5 is the reason RV770 uses a 256-bit bus instead of a 512-bit bus.
i.e. GDDR5 does matter, because it allows them to use a smaller bus, therefore a smaller GPU, while still having enough memory bandwidth to feed the GPU.

Also, memory speed itself doesn't determine GPU speed. It's only necessary to have the video memory fast enough to saturate the GPU with instructions.
Although no memory controller or prefetching system is perfect, more speed is practically unnecessary past a certain point (that point depends on the GPU), and will only yield marginal if any gains.

The larger GPU itself, as well as the more traces needed on the PCB (because of the larger bus) make G200 cards significantly more expensive to make. Basically, RV770/790 can always be priced lower to give a better price/performance.

 

[tastegw]

i just hope the gtx 350 romur is true.

512-bit with gddr5

that would be a monster.

 

[Apokalipse]

i just hope the gtx 350 romur is true.

512-bit with gddr5

that would be a monster.

only if the GPU needed that kind of memory bandwidth to keep its shaders busy.

I'd go with as small bus as is practical for the performance of the GPU. GDDR5 makes it possible to use a smaller bus while maintaining high bandwidth.

 

[gurusan]

i just hope the gtx 350 romur is true.

512-bit with gddr5

that would be a monster.

As Apok said, only if the GPU actually was able to use it....do some game benches with your card at 100gb/sec and 140gb/sec. The difference will be 1-2% ..

 

[zedman3d]

Wow! The 4890 is already for sale in Australia!
Gigabyte Radeon HD4890 Gigabyte Radeon HD4890 [GV-R489-1GH-B] - $489.00 : PC Case Gear, Quality case accessories and components

 

[Poizen22]

Re: HD 4890 vs GTX 275 – Specs Leaked

try this on for memory bandwidth.



my card overclocked that's serious business.

(also i have the 55nm version, i need to update GPUZ to the latest version.

This is the best I could find 3 pages deep into google image search, I'm sure there is better, with all the extreme OC's out there.

zmatt look he beat that. and i listed the highest factory oc from nvidia vs the highest factory oc that pudle named, and it was still higher. gddr5 over a 256bus is almost as fast at a fraction of the price, but none the less the 448bit bus is faster. its close they are tight indeed, but the 260 line has higher mem bus.

 

[Apokalipse]

zmatt look he beat that. and i listed the highest factory oc from nvidia vs the highest factory oc that pudle named, and it was still higher. gddr5 over a 256bus is almost as fast at a fraction of the price, but none the less the 448bit bus is faster. its close they are tight indeed, but the 260 line has higher mem bus.

Why are you arguing over memory bandwidth?
It only needs to be fast enough to saturate the GPU with instructions.

 

[philbar71]

that's not my daily clocks though. it's stable enough to play about 30 mins of crysis then it starts artifacting like crazy

 

[zmatt]

zmatt look he beat that. and i listed the highest factory oc from nvidia vs the highest factory oc that pudle named, and it was still higher. gddr5 over a 256bus is almost as fast at a fraction of the price, but none the less the 448bit bus is faster. its close they are tight indeed, but the 260 line has higher mem bus.

That's the fastest i did with a 30second Google search. I can do better if it means that much to you.