Huddy says "R600"

I just bethought of this post...

[dreaming]If R600 has more texture power, it needs more bandwidth. If core speed scale at a similar ratio to memory speed, we won't get the necessary amount of bandwidth from faster memory modules. So the only way to increase bandwidth is...?[/dreaming]

 

Actually G80 right now have some problems in supporting GDDR4 .
But you will see 7800GTX 512 style occur again........

Form someone who is responsible for R600 board told me If he is optimistic on time frame for R600 Launch , He would guess Feb at least. But R600 is beast which would literally sip all the power supply.

 

You're just a barrel o' good news aren't ya

 

G71 is a cash cow can make Nvidia more than 3~5 times Gross Margin of G72 .

sometimes faster means combination of Faster Ram / Higher-Clock/ Better and noisy fan .

 

Hmm in what sense? are you saying there is GDDR3 ram shortages at the required speeds? Or core clock is causing issues with the g80? Or are you talking about the r600 lol, I've lost something in the middle there.

 

Nvidia want to repeat " High Volume 7800GTX 256MB to Limited 7800GTX 512MB version" again.

 

AHHH ok well that depends if they only need it of course.

Anyways, I haven't heard any issues with GDDR4 and the g80, are you talking about latancy issues for the ram and the memory controller of the g80 not being able to handle the higher latancy?

 

With only 500M transistors?
They've got to be clocking it pretty fast, then, no?

 

maybe. cause my friend didnt mention in detail.

 

If your friend mentioned it, how did he come to that conclusion, then? Either he has something substancial to say or he´s just guessing.

 

some problem lies in ATI always want to do everything on their own without procuring any IPs

to speeding up whole progress .

 

Hard to beleive that a pair of these things in crossfire could actually have more bandwidth than Xenos's eDRAM all to a full 1GB of memory !

Incidentally, I don't expect R600 to come with only 64 Xenos style unified shaders, it isn't enough.

At 650Mhz it would only have as much total shader power as R580 has in its pixel shaders alone. Add in the vertex shaders and R600 would need to run at 740Mhz just to match R580's total shader power. That seems far too little for a next gen, DX10 part with a monster 512bit memory bus.

I expect 96 units at 600+ Mhz.

 

I aggree. It might be plausable if this was a first attempt at a unified architechture, but after getting it right with Xenos, there's no way that R600 will only be on par with the R580 generation product. It's got to do a lot better than that.

 

Well did they get it right with Xenos though? Is its performance impressive given clock speed and number of units?

 

Play the rough theoretical FLOP game. 650*9*64 (374) for R600 vs 650*(48*8+8*10) (302). I think Xenos loses an ADD per shader compared to R580. So yeah it does look like by the numbers R600 should come out on top. Don't know about smoking though.

Edit: Corrected calculation based on Dave's feedback.

 

Sure. We know R580 packs 374.4 GFLOPS in the pixel shaders and another 52 in the vertex shaders for a total of 426.4 GFLOPS across all shaders.

So for R600 to use 64 Xenos style shaders would mean 64*9 FLOPS per cycle or 576 FLOPs per cycle.

576*0.65 = 374.4 GFLOPS

 

Xenos is Vector MAD + Scalar ADD (and special function). 216GFLOPs.

 

The R580 ALU's make up 12 FLOPS including the ADD while Xenos's Scalar is not MADD capable and thus only accounts for 1 FLOP (for a total of 9) - I realise it may be capable of more under certain circumstances but 9 is probably the best figure to use for a Xenos ALU.

So its more like 650*9*64 (374.4) vs 650*(48*12+8*10) (426.4).