Replies to post #6922 on Advanced Micro Devices Inc (AMD)

[Elmer Phud]

Spokeshave -

Now that you no longer have the power to delete embarrassing posts I have taken you off ignore.

Where are you getting 193mm^2? I have not seen a die size for A64 published yet, and it seems that you are assuming that A64 will be the same size as Opteron. That is not a fair assumption.

I am assuming that Opteron and A64 are the same die. I don't know that for a fact but it seems most likely to me. As they both have the same 1Meg of L2 it would make more sense to just use the same die. The cost of maintaining 2 designs and doing 2 sets of bug fixes, speedpath fixes, transistor revs etc would be too much for a company on a limited budget. With the low volumes expected early on it just wouldn't make sense. The 256K version though probably is a different die.

Could I be wrong? Sure, but that's my guess.

[Haddock]

I have not seen a die size for A64 published yet, and it seems that you are assuming that A64 will be the same size as Opteron.

Check out http://www.investorshub.com/boards/read_msg.asp?message_id=1117124 and its predecessor. I guess it's worth mentioning that the superfluous 13.5% (for the 2nd DDR interface and the 2 extra HT controllers) isn't as far as one can see placed in such a way that you can cut them off and still have a rectangular die. On the other hand the die without DDR interfaces and HT interfaces is rectangular, so that would on the face of it provide a good basis for an A64 with no space wasted. I would imagine that the paths to those two modules would be less performance critical than most other paths in the CPU, so you aren't relaying out the most critical parts if you redo them.

http://www.amdzone.com/articleview.cfm?ArticleID=1270

The gross size of A64 looks to be 167mm2. About 100mm2 of that is cache.

[jhalada]

spokeshave,

It depends on what kind of volume AMD is planning on for 1 MB Athlon 64. If the volume they are planning on is modest (less than 1M per quarter) they can save resources by just using Opteron die.

The real savings in die space will happen when AMD introduces 256K Athlon 64 for low end. And, 1 MB Athlon 64 will move to 90nm, probably (or hopefully) in Q1 2004.

Joe