RawTherapee can’t use a GPU, it is CPU only.
darktable uses OpenCL for its GPU acceleration, and both AMD and Nvidia support OpenCL. Newer AMD.cards that support their ROCm driver will be the easiest install on Linux
Hello @asn
and don’t have all the CPU bugs Intel has. Each new Intel bug reduces performance by ~3%. So with a current Intel CPU you loose 18-30% performance the mitigations depending on the workload
I was extremely surprised about your statement.
I am fully aware of the huge past bugs concerning Intel CPUs and the consequent damage related to their performances.
However, I have never read about this vast problems still present in their current CPUs.
Can you support your view with some benchmark?
For instance, If you take a look at some on-line benchmarks comparing:
Intel I7 CPU 8850H vs Intel I7 9850H
The 9850H, the new CPU, is always faster in every comparison I have checked…
Of couse, there is not a big difference between the 2 contenteders, but it is present and documented.
Disclaimer:
Personally, I have always suggested to buy Intel I7 CPUs even though they are more expensive than the “corresponding” AMD CPUs (therefore my opinion is totally biased…).
As regards the new Intel I7 CPUs released every year or so, the improvements in terms of speed are not generally outstanding and I often suggest to buy the previous version to spare some money…
As an aside, I think that since the Intel CPUs are more widespread (at least in Italy) they are more tested than the AMD CPUs. Therefore, it is easier to reveal their flaws and bugs 
He’s not talking about a new vs an old processor, but rather the same CPU running with security patches vs without security patches. You can see those benchmarks here: https://www.anandtech.com/show/12566/analyzing-meltdown-spectre-perf-impact-on-intel-nuc7i7bnh/4
Meltdown and specter are pretty old, and there have been more bugs found since then.
Shockingly, Intel continues to patch these issues in software, instead of fixing it in hardware, even in the most current CPUs.
Yes, newer CPUs are faster and better, but you loose a certain amount to the mitigations of the CPU bugs, and with every new bug they find it is adding a 3-5% performance loss. It was at 13% and now 4% with the latest where added. So you have a fast CPU and someone constantly stands on the break to slow it down.
The upcoming AMD mobile processor look very interesting. With 7mn technology, you will probably get great performance with long battery time.
Somewhere I can’t find now, I read that the real performance hit an average user would appreciate may be around 5-10%, because not every performance loss affects the user every time his/her computer is used. And of course all the performance losses doesn’t occur simultaneously. So to me, it’s a bit adventurous saying that a new Intel CPU will have a performance loss around 18-30%. That’s a bit too much, I guess.
Following your links, I’ve read that Coffe Lake processors are affected by those new bugs, too. If we agree with your numbers, and the numbers in this comparison:
https://cpu.userbenchmark.com/Compare/Intel-Core-i7-8700-vs-Intel-Core-i7-4790/3940vs2293
Don’t you think that a 20-30% performance loss in the 8700 would be a bit too much to believe it? Remember that in real life systems many situations are processed with just 1 core, so (if be believe this comparison) it means that an i7-8700 processor is effectively much slower than an ancient i7-4790.
In spite of this, I agree with you that a brand new processor with lower TDP would be highly desirable in a laptop
As I’m a software developer I need my CPU mostly for compiling software. With the Intel hardware bugs, for example compiling Android took 10 minutes longer after all those bugs have been fixed in software. It always depends on your workload for some you don’t really recognize it and for some other is it a lot.
I can only speak about the desktop but the latest AMD CPUs are amazing, especially for that price. And it is not only that they are faster, I have PCIe 4.0 and that gives me a lot of IO throuput with my NVMe disks.
I’m sure the AMD mobile processor will have a good price especially for great performance and low power.
I wouldn’t buy a notebook until they are out. Also it is very likely that the Intel mobile processor prices will drop in price like they did when Ryzen’s came out.
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The problem is that fixing those issues in hardware without a hit on performance is extremely hard. It requires essentially a whole new approach to speculative execution. The current approach took a couple of decades to develop…
I think this is a nice explanation of the problem for those interested in the details: https://spectrum.ieee.org/computing/hardware/how-the-spectre-and-meltdown-hacks-really-worked
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Here it is - i am typing on it now: a 2015 i7 Thinkpad with 32 GB of RAM, 1 TB SSD and the “standard” full HD display. It’s fast and I don’t know what beef you have with the display. it’s bright and absolutely OK.
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Get your hands on a hardware screen calibration device and run displaycal. What percentage of sRGB is it covering? Let me know. Maybe they’ve gotten better.