Monero(XMR) GPU better than CPU mining

[Etherion]

This is interesting: With Monero a I7 4790 runs at 300 H/S using 90W power.  My RX480 runs at 730 H/S using 110W. The RX cards use half the power than CPU. I really did not expect this to be the case.

[nu1mlock]

Everyone else expected this.

[cptfisher]

NO WAY MAN ! you just now discovered the hot water  !!!! YOU ARE GONNA CHANGE THE WORLD !

[Emoclaw]

Why did you not expect this? GPU cards (where OpenCL i.e AMD is concerned) will always be faster and/or more efficient than CPUs in any given Proof-of-Work algorithm.
The CryptoNight algorithm was designed to be GPU resistant, but this means nothing once GPU miners are actually released.

Scrypt was meant to be GPU-resistant as well, and there are ASICs now.

[Vaccinus]

yeah i think yes, they are better because you have more gpu in one rig than cpu, but the hashrate/watt ratio is not that different, unless perhpas you use a heavily optimized kernel, for amd i've look around and a 470 can do 700hash, which is very high a cpu can't reach that

[toygg]

One way to visualize it is a CPU works like a small group of very smart people who can quickly do any task given to them. A GPU is a large group of relatively dumb people who aren't individually very fast or smart, but who can be trained to do repetitive tasks, and collectively can be more productive just due to the sheer number of people. Thus, the GPU are way better at mining then CPU.

[ol92]

Why did you not expect this? GPU cards (where OpenCL i.e AMD is concerned) will always be faster and/or more efficient than CPUs in any given Proof-of-Work algorithm.
The CryptoNight algorithm was designed to be GPU resistant, but this means nothing once GPU miners are actually released.

Scrypt was meant to be GPU-resistant as well, and there are ASICs now.

I don't think Cryptonight was meant to be gpu resistant, but to be asic resistant and to provide balanced performance between gpu and cpu.
You have some algo which are meant to be gpu resistant, in order that gpu performance will not be superior than cpu.
For instance lyra2z330.

For monero with my xeon E5 2696V3 (two years old model, 800$ on ebay), with some bios hack, I have around 940h/s with xmr stack miner, with around 135-140W, which is not bad.

[QuintLeo]

Why did you not expect this? GPU cards (where OpenCL i.e AMD is concerned) will always be faster and/or more efficient than CPUs in any given Proof-of-Work algorithm.
The CryptoNight algorithm was designed to be GPU resistant, but this means nothing once GPU miners are actually released.

Scrypt was meant to be GPU-resistant as well, and there are ASICs now.

 Ryzen is actually proving to be competative on efficiency for XMR vs any GPU (possible exception for the GTX 750 ti, but that thing seems to have hit THE sweet spot on XMR).

 Some of the more modern Intel CPUs are pretty efficient too.

 pre-Ryzen AMD CPUs though are definitely NOT XMR efficient by current standards, nor are pre-Maxwell NVidia GPUs or pre-RX AMD GPUs (possible exception for the Fury/FuryX/Nano?).



 OP, keep in mind that your particular I7 model is a few generations old now, and at LEAST one if not 2 process nodes behind current state-of-the-art - of COURSE it is less efficient than stuff running on a CURRENT process node.

[bathrobehero]

This is interesting: With Monero a I7 4790 runs at 300 H/S using 90W power.  My RX480 runs at 730 H/S using 110W. The RX cards use half the power than CPU. I really did not expect this to be the case.

CPUs have like 4-16 powerful cores while GPUs have something like 2000-3000 cores - typically speaking.

Now imagine each CPU core being like a super strong and heavy fighter and each GPU core being a small but nimble kid.

If you're still following, hashing algorithms are like picking up berries from the ground; thousands of kids are much better at it than a few strong dudes...

[antantti]

This is interesting: With Monero a I7 4790 runs at 300 H/S using 90W power.

One of my laptops can do 110h/s using only +20w when mining, it kills all my desktop i5's and i7's in terms of w/h. And is really close to best gpu's.

[GabryRox]

OP: are you sure that CPU is using all 90W to mine XMR?  That seems almost 2x too high to me as Im running the exact same CPU (assuming your is also 4790K) and it only uses maybe 40-45W mining at that same 300 hash-rate.

I'm not 100% sure about this but do you happen to be running it on all 8 threads?  In case you didn't realize, CPU mining XMR requires 2MB of cache per thread, so you actually don't get any more hashes using 8 threads vs 4 since this CPU only has 8MB of cache.  I tested this extensively only this CPU as well as a 6800K and 2600k and that holds true on all 3 of them. The 6800k can do 7 threads mining XMR effectively (about 355 hash rate, with 15MB of cache) but if you try to push it to 8 or above, the hashes wont improve and in some cases even went down.  I don't remember the effect on power consumption though but at least something to check if you haven't already. No sense throwing away wattage for no extra hashes, right?