Post
Topic
Board Altcoin Discussion
Re: Advanced Hardware, SHA256 and Scrypt questions
by
turtle83
on 28/04/2013, 09:58:52 UTC
Isint GPU memory external RAM? Or is that a whole different ballgame cause of high clock frequency?

GPU have L1/L2 cache hierarchy just like a CPU.  SCRYPT only performs well if it is small enough to fit into on-chip memory.  If you have to go off-chip, it's going to be a turd.  But yes, most graphic cards have seemingly endless amounts of external memory.

The SCRYPT configuration used in Litecoin needs 128KB, which fits easily into onchip cache in a CPU/GPU, and into onchip block memory on many (not all) FPGA.



I dont think so... I use cgminer on my 7950 with :-
Code:
--thread-concurrency 25768

Meaning its using 25768 * 128 KB of memory (roughly 3.14 GB) . On increasing the concurrency, cgminer fails on startup saying im trying to allocate more memory than available.

That or ive misunderstood the purpose off thread-concurrency