Well, duh, of course it was CPU-only at the start. I'm asking if the intent was to make it easier on GPUs than Quark.
I think he just did it his own way, as he didn't know about Quark, which is the impression I got long ago when I asked - don't ask me to find proof, I'll not waste my time. Just giving you an answer if you're interested.
I suppose it's possible. Meh, hardly matters, I suppose. I just want to know his intentions for the PoW - what qualities he wanted it to have.
I think Evan should chime in..that is the best answer
even at
https://dashpay.atlassian.net/wiki/display/DOC/X11 Created by Balazs Kiraly, last modified on Jun 01, 2015
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the author said:
It was probably inspired by the chained-hashing approach of Quark, adding further “depth” and complexity by increasing the number of hashes, yet it differs from Quark in that the rounds of hashes are determined a priori instead of having some hashes being randomly picked.
The X11 algorithm uses multiple rounds of 11 different hashes (blake, bmw, groestl, jh, keccak, skein, luffa, cubehash, shavite, simd, echo), thus making it one of the safest and more sophisticated cryptographic hashes in use by modern cryptocurrencies.
The name X11 is not related to the open source GUI server that provides a graphical interface to unix/linux users.
Balanced CPU/GPU mining
When Darkcoin was initially launched with X11, it was only mineable through CPU mining programs.
After a spike in the Darkcoin network hashrate in early February 2014, it was speculated that someone might have made a GPU miner and thus a bounty of over 3000 DRKs was given in order to assist in the creation of a GPU miner client that could be publicly available, for fairness reasons.By mid-February the GPU client was launched and by late-February it was optimized for higher hashrates. At the same time, the CPU mining clients evolved to increase their speed by using the SSE2/3/4, AVX and AES instruction sets.
At that point it became evident that the hashrate difference between GPU and CPU implementations were not that chaotic, although GPUs still took the crown in terms of energy efficiency. Top of the line and tuned CPUs, like a 6-core i7s running at 4.5 GHz produced 880 khashes/second when GPUs like AMD's 280 and 290 gave 3 times as much.
A ratio of 1:3 was thus established for the fastest CPUs versus the fastest AMD GPUs – which is significantly better than Scrypt or SHA256 and allowing CPU users to mine X11 coins. By June 2014, the ratio had gone up to 1:6 due to the evolution of GPU mining programs and relative stability of CPU mining programs.
It should be noted that these ratios are more a reflection of the mining programs rather than an inherent property of the algorithm itself and thus the ratios can change depending the development progress of the CPU and GPU mining clients.
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is that you wolf0 that got 3000 DRK?
i highly doubt Evan didn't know about Quark, Quark was months ahead of dash launch
(blake, bmw, groestl, jh, keccak, skein) Quark
(blake, bmw, groestl, jh, keccak, skein, luffa, cubehash, shavite, simd, echo) X11
Haha, no. I would be ashamed to have written that miner.