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KlimtMed

macrumors newbie
Jun 5, 2017
7
0
USA
Is there a significant speed difference between Broadwell 3.1 Ghz quad-core i5 and Kaby Lake 3.0 Ghz quad core i5?

Trying to learn about processors, if there is a better place on the forum to discuss them please point it out to me :)
 

Shivetya

macrumors 68000
Jan 16, 2008
1,669
306
Is anyone going to consider not upgrading to any of the new iMacs but instead purchase a MacBook Pro as a desktop replacement?

I tried the laptop route once, found it never left my desk so I stopped that silliness right then and there. I use my phone/ipad if I need mobile work
 
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potatis

macrumors 6502a
Dec 9, 2006
840
291
Is there a significant speed difference between Broadwell 3.1 Ghz quad-core i5 and Kaby Lake 3.0 Ghz quad core i5?

Trying to learn about processors, if there is a better place on the forum to discuss them please point it out to me :)

The later processor is always faster, but maybe not much, 5% or so at the same frequency I read. So since Skylake is inbetween them and 0.1GHz is negliable maybe 10% faster? Kaby Lake should be faster when playing HEVC video though.
 

Appleaker

macrumors 68020
Jun 13, 2016
2,197
4,194
I plan on holding out for the iMac Pro. I'm very disappointed with the GPU options. I was really hoping to get a nVidia 1070 or 1080 performance equivalent, but we instead get a Radeon 580 that is about 5% below a 1060.
I think most of us were hoping for Nvidia 1000-series cards but at the same time Apple, has official support for external GPUs coming so it's not all bad news.
 

padaxax

macrumors member
Oct 31, 2015
42
19
Would like to know whether the egpu can be used on internal screen of the new imac
 

Glideslope

macrumors G3
Dec 7, 2007
8,333
5,793
The Adirondacks.
Fusion or SSD? That is the question and any info greatly apprecialted!

Thats really is a question of how deep is your budget/need. I'm ordering a 2T Fusion. With it's 128g of SSD it will be enough for my needs. I also know someone who ordered a 27" with a 2T SSD. Insanity IMO, but they will write it off as a business expense. :apple:
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I was surprised the Crucial memory was a bit slower (higher CL) but I still think they're good products & we are only talking fractions of a second.

Agreed. Wonder who makes it? :apple:
 

richinaus

macrumors 68020
Oct 26, 2014
2,432
2,187
I tried the laptop route once, found it never left my desk so I stopped that silliness right then and there. I use my phone/ipad if I need mobile work

I agree. My biggest [tech] regret was getting a laptop instead of the 2015 iMac. Not doing that again and just ordered a maxed iMac :)
 

yadmonkey

macrumors 65816
Aug 13, 2002
1,321
853
Western Spiral
Is it right to think that Kaby Lake i5 is not that much faster than the 4 year old Haswell i5 from the 2013 iMac?

CPU benchmark rates 7054 for the old 3.2 GHz i5 and 7971 for the 3.4 GHz i5 - maybe 10-15% faster? Shouldn't it be much better 4 years later?

Kaby Lake isn't all that much faster. More importantly for a machine that can play 4K, it supports HDCP2.2. Also it supports Thunderbolt 3 and USB 3.1. Some great features and modest gains in performance.
 
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KlimtMed

macrumors newbie
Jun 5, 2017
7
0
USA
Wow I had no idea that Netflix security measures require kaby lake to stream in 4k, AND my 25Mbps internet speed isn't even good enough to stream in 4k!

I question the value of a 4k screen when really, the only time I would use 4k is when I'm looking at pictures from my iphone. I stream baseball games in HD but that would still look great on a 1080p. I should probably just get a 1080p screen and use savings for SSD, processor, RAM...
 

yadmonkey

macrumors 65816
Aug 13, 2002
1,321
853
Western Spiral
Wow I had no idea that Netflix security measures require kaby lake to stream in 4k, AND my 25Mbps internet speed isn't even good enough to stream in 4k!

I question the value of a 4k screen when really, the only time I would use 4k is when I'm looking at pictures from my iphone. I stream baseball games in HD but that would still look great on a 1080p. I should probably just get a 1080p screen and use savings for SSD, processor, RAM...

I think 25Mbps will be fast enough to stream 4k and don't forget that Kaby Lake supports h.265, which allows for 4k streaming at lower bitrates. I'm certain Amazon and Netflix will be all over supporting this if it means they can save money on bandwidth.
 
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KlimtMed

macrumors newbie
Jun 5, 2017
7
0
USA
I think 25Mbps will be fast enough to stream 4k and don't forget that Kaby Lake supports h.265, which allows for 4k streaming at lower bitrates. I'm certain Amazon and Netflix will be all over supporting this if it means they can save money on bandwidth.

I pay for "up to 25 Mbps" and I usually clock it somewhere between 18-21. Netflix recommends 25 Mbps but according to random internet sources, you really only need 16 if you're not passively taxing the system with 10 other devices.

I haven't heard of h.265 until now... after a self-driven crash course... does anyone know what kind of bitrates are possible? And yes it makes sense that streaming services would want to push that number down.

this is off topic, please excuse my ignorance... any recently produced mac should be able to handle low intensity web surfing on screen #1 while streaming 1080p to a second screen, yes? would this require usb-c/thunderbolt3 or should thunderbolt 2 be enough? sorry im not tech-oriented, but i am goal-oriented and when getting a new comp I like getting bang for my buck lol. debating refurbished 2015 imac vs. 2017.
 

Trebuin

macrumors 65816
Jun 3, 2008
1,494
272
Central Cali
I pay for "up to 25 Mbps" and I usually clock it somewhere between 18-21. Netflix recommends 25 Mbps but according to random internet sources, you really only need 16 if you're not passively taxing the system with 10 other devices.

I haven't heard of h.265 until now... after a self-driven crash course... does anyone know what kind of bitrates are possible? And yes it makes sense that streaming services would want to push that number down.

this is off topic, please excuse my ignorance... any recently produced mac should be able to handle low intensity web surfing on screen #1 while streaming 1080p to a second screen, yes? would this require usb-c/thunderbolt3 or should thunderbolt 2 be enough? sorry im not tech-oriented, but i am goal-oriented and when getting a new comp I like getting bang for my buck lol. debating refurbished 2015 imac vs. 2017.

Think of it this way, 265 is a compression method, but so work intensive that it is not practical. How do they make it practical? Think of a kid at school doing math with nothing but paper & pencil vs a kid with a calculator. That calculator represents the new tool or tweak a CPU has designed in it. All of those CPU features a specifically designed to do some exact type of math, so in theory it would bench far better if it only benched using that math equation.
 

KlimtMed

macrumors newbie
Jun 5, 2017
7
0
USA
Think of it this way, 265 is a compression method, but so work intensive that it is not practical. How do they make it practical? Think of a kid at school doing math with nothing but paper & pencil vs a kid with a calculator. That calculator represents the new tool or tweak a CPU has designed in it. All of those CPU features a specifically designed to do some exact type of math, so in theory it would bench far better if it only benched using that math equation.

I understand that kaby lake makes h.265 functional. the question is, to what degree does h.265 reduce the necessary bitrate of 4k streaming? down to 25 Mbps? 20? 15? I could have the most advanced CPU on earth, if my ISP limits my download speeds to 2 Mbps, I wont be able to stream 4k.

It sounds like my download speeds of about 18 Mbps should be able to manage 4k streaming, as long as the CPU is compatible with their anti-pirating measures (i.e., kaby lake or no go).

Thanks to everyone for their contributions to this discussion. This forum has been super helpful to me over the last few days.
 

Trebuin

macrumors 65816
Jun 3, 2008
1,494
272
Central Cali
I understand that kaby lake makes h.265 functional. the question is, to what degree does h.265 reduce the necessary bitrate of 4k streaming? down to 25 Mbps? 20? 15? I could have the most advanced CPU on earth, if my ISP limits my download speeds to 2 Mbps, I wont be able to stream 4k.

It sounds like my download speeds of about 18 Mbps should be able to manage 4k streaming, as long as the CPU is compatible with their anti-pirating measures (i.e., kaby lake or no go).

Thanks to everyone for their contributions to this discussion. This forum has been super helpful to me over the last few days.

You're probably not going to like this answer, but from what I have read, 265 uses approximately 40-50% less space than 264. That being said, it depends on Netflix at the time. They should advertise that, but probably won't. It'll be trial & error.
 
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rogerdox14

macrumors newbie
Jul 3, 2017
1
0
Does anyone know if the 1TB Fusion Drive has a 24GB or 128GB SSD? I cannot find it anywhere

Actually it's now a 32GB SSD on the 1TB Fusion Drive (a slight upgrade from previous years, but still not very impressive). To get a 128GB SSD you still need to get the 2TB or 3TB Fusion Drive.

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I'd appreciate some speculation/conjecture: will the top end i7/580 iMac be suitable for gaming?

I'd install a Windows partition for gaming and not looking for the be-all-end-all in gaming performance, but... can it game at all in 4K and if not, will lower resolutions look crappy?

I can't answer the 4k question (though my guess is you'd often need to use resolutions below 4k to get a decent frame rate, and that any of the iMacs with Radeon graphics should be a pretty fair Windows gaming machine, albeit quite a bit pricer than an equivalent non-Apple-made Windows gaming machine).

However, one thing I would point out: if you get an iMac with a fusion drive, while you can make a Windows partition on that for Boot Camp, that Windows partition will be just on the hard disk part of the fusion drive and will get no speed benefit from the SSD part of the fusion drive. So on Windows, system boot up will be slower, and for large Windows games with a lot a graphics on disk, you may get some graphics-loading-from-disk stutter, for example on entering a new area or whatever (this would also be a reason to the best graphics card with the most video memory you can afford -- i.e. the 580 you are planning on -- to maximize the memory available for caching graphics, so graphics loading happens less often). So if you plan to use a Boot Camp Windows partition much and you can afford it, you might want to consider getting an SSD instead of a Fusion Drive. Of course, an SSD big enough to hold both your Mac partition and your Windows Boot Camp partition probably won't come cheap (at least from Apple). If you find yourself short on space, I'd recommend getting an external USB hard drive as well and offloading non-speed-critical space hogs like videos, your iTunes music library, or your photo library to that.
 
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