27 inch 3.4GHz or 3.5GHZ ?

ocsupersonic

macrumors newbie
Original poster
Nov 29, 2012
28
5
England
Just looking for advice/a prod, looking to pull the trigger on updating my 27-inch Late 2012 2.9GHz iMac and can't decide on the 3.4GHz with 8GB RAM and the 512GB SSD or the 3.5GHz .
Main uses will be monitoring/trading stocks and shares, Betting/watching races, playing poker, light gaming (old stuff on steam Half-life and the like) and general surfing.
Is it worth getting the mid range one or do I just get the base model ? will be upgrading the RAM whichever way I go.
Cheers in advance
Paul
 

mcomp112

macrumors regular
Jan 1, 2017
111
28
3.4/570 is the best iMac 2017 configuration.

You will likely notice no difference at all between the two in performance but the 3.5/575 will run warmer than the 3.4/570.
 

Tjmckay4

macrumors member
Apr 24, 2014
92
22
Perth, West Aus
Thanks ocsupersonic, I was just about to start a thread with the same exact question.

Sorry to hijack/go on a tangent... what about the difference for photo (lightroom CC) and light 4k (iMovie/Premiere Pro CC) editing?

Does the 575 over much of a difference over the 570? A$286.50 difference between the base and mid for me. That money could go towards RAM and external drive(s).
 
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Chupa Chupa

macrumors G5
Jul 16, 2002
14,834
7,394
I just bought the entry level 3.4Ghz. After comparing the various models, from a purely value perspective, if you want a decent Mac the entry level is the way to go. If you want real performance than the top end 3.8Ghz is a better value than the middle 3.5Ghz model with much faster CPU and GPU and double the VRAM, and if you'll be using it 2x HDD storage -- all for $300 more.

Of course 8GB RAM is worthless. I bought a 16GB Corsair Vengence kit from Jet.com for a tad over $100 after 15% discount. Also bought a basic 1TB SSD as my boot drive and to store documents. I don't like using the iMac's internal drive because if it fails you are without a comptuer until its fixed. I'd rather be able to just unplug the failed drive and plug in a new one and get back to work. Also Apple's prices for RAM and SSDs are nuts, as always.
 

EugW

macrumors G3
Jun 18, 2017
8,423
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I just bought the entry level 3.4Ghz. After comparing the various models, from a purely value perspective, if you want a decent Mac the entry level is the way to go. If you want real performance than the top end 3.8Ghz is a better value than the middle 3.5Ghz model with much faster CPU and GPU and double the VRAM, and if you'll be using it 2x HDD storage -- all for $300 more.
The Turbo Boost speeds of the 3.5 and the 3.8 are nearly identical, but the 3.5 is a 65 W class chip. The 3.8 is a 91 W class chip. Some testing has the 3.8 running pretty cool too, but under extreme conditions, the 3.8 heats up way more than the 3.5. Also, the 575 that comes with the 3.5 is considerably faster than the 570 that comes with the 3.4.

Those factors may or may not be relevant to you.

Of course 8GB RAM is worthless. I bought a 16GB Corsair Vengence kit from Jet.com for a tad over $100 after 15% discount. Also bought a basic 1TB SSD as my boot drive and to store documents. I don't like using the iMac's internal drive because if it fails you are without a comptuer until its fixed. I'd rather be able to just unplug the failed drive and plug in a new one and get back to work. Also Apple's prices for RAM and SSDs are nuts, as always.
Is it this one, and have you verified it works in Macs?

http://www.corsair.com/en-gb/vengea...m-2400mhz-cl16-memory-kit-cmsx16gx4m2a2400c16

Because those CL specs don't match the specs of the iMac's stock RAM. Sometimes when you have non-matching RAM like that, it may not boot, or it may boot at a lower speed. Good luck.
 

Chupa Chupa

macrumors G5
Jul 16, 2002
14,834
7,394
http://www.corsair.com/en-gb/vengea...m-2400mhz-cl16-memory-kit-cmsx16gx4m2a2400c16

Because those CL specs don't match the specs of the iMac's stock RAM. Sometimes when you have non-matching RAM like that, it may not boot, or it may boot at a lower speed. Good luck.
Yes that's the one. I verified with Corsair tech support before I bought because, yes, I have a lot of experience with installing RAM in Macs and know they are extra finicky. Also one of the guys over at 9to5 Mac installed the 32GB kit and wrote up an article on it working great.https://9to5mac.com/2017/06/21/how-to-upgrade-ram-2017-5k-imac-video/

And, yes I will be pulling the stock RAM -- again, as having experience with Mac RAM, installing RAM even from the same manufacturer but a different lot# can summon the ghosts in the machine.
 

EugW

macrumors G3
Jun 18, 2017
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Yes that's the one. I verified with Corsair tech support before I bought because, yes, I have a lot of experience with installing RAM in Macs and know they are extra finicky. Also one of the guys over at 9to5 Mac installed the 32GB kit and wrote up an article on it working great.https://9to5mac.com/2017/06/21/how-to-upgrade-ram-2017-5k-imac-video/

And, yes I will be pulling the stock RAM -- again, as having experience with Mac RAM, installing RAM even from the same manufacturer but a different lot# can summon the ghosts in the machine.
Someone in another thread said with I think Kingston RAM with slightly different specs, it would run alone fine at 2400 MHz, but with the stock RAM it all ran at 2133 MHz. But if you're pulling the stock RAM, then that wouldn't be a factor.

I just got 16 GB RAM with the exact same specs from Crucial, and it runs fine with the stock RAM at 2400 MHz, for a total of 24 GB. It didn't matter what order I had the RAM either. Always ran fine.

But now that RAM is just sitting on my desk because I returned my i7. :( My i5-7600 is due to arrive Wednesday. :)
 

whatevs

macrumors member
Apr 3, 2008
58
10
SF
Also, the 575 that comes with the 3.5 is considerably faster than the 570 that comes with the 3.4.
will you share some feedback on your i5/575 system when it arrives?

I'm torn between the 3 i5 tiers (given up on i7 as I don't need the performance). I usually just go for the mid-tier with Mac purchases but this new iMac has me stumped on the best choice. I know I'll get an 512 SSD and upgrade the RAM to 24 myself.
 

cynics

macrumors G4
Jan 8, 2012
11,586
1,886
My opinion on this varies from some others.

The CPU itself would be impossible to notice a difference in the task you listed. And in reality the max benefit you'll see in very specific task will be about 10% faster performance. So even if your work load changed to using a very CPU intensive task that 10% still might be hard to notice and difficult to justify the extra expense.

However with the 3.5ghz model (i5-7600 btw) you'll also be going from the Radeon Pro 570 to the 575. In gaming you (we) are more sensitive to GPU performance because in gaming the GPUs output is in real time. Its easy to see poor frame rates, bad frame timing and pacing, and even worse the requirement for you to manually lower graphic fidelity to maintain the aforementioned frame rates.

I don't have any benchmarks but we can compare computational power difference between them. The 575 has 20% better floating point performance and 20% better texture fill rate performance. You may have heard of the word teraflops will comparing performance of GPU's, teraflops in and of itself doesn't mean too much however when comparing the same GPU architecture its a fair way of determining performance. That said the 570 is 3.5 teraflops and the 575 is 4.5 teraflops. Assuming this source is correct that is.

My advice is to do your research and decide for yourself. In any event the software and games you listed will run fine on either however the 575 might give you a little more head room and you might be able to set those graphics from low to medium or medium to high with it in games in the future.
 

EugW

macrumors G3
Jun 18, 2017
8,423
5,792
I don't have any benchmarks but we can compare computational power difference between them. The 575 has 20% better floating point performance and 20% better texture fill rate performance. You may have heard of the word teraflops will comparing performance of GPU's, teraflops in and of itself doesn't mean too much however when comparing the same GPU architecture its a fair way of determining performance. That said the 570 is 3.5 teraflops and the 575 is 4.5 teraflops. Assuming this source is correct that is.
580: 5.5 Teraflops
575: 4.5 Teraflops
570: 3.6 Teraflops

http://creators.radeon.com/radeon-pro/

Thus, the 575 is a 25% improvement in Teraflops over the 570.
 
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SaSaSushi

macrumors 601
Aug 8, 2007
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jace88

macrumors regular
Jan 3, 2011
207
13
Sydney, Australia
Thanks everyone in this thread... I'm also looking at the different specs now comparing the three i5 models, but also wondering if a spec bump is due soon anyway with WDWC.
 

mreg376

macrumors 65816
Mar 23, 2008
1,134
328
Brooklyn, NY
Just looking for advice/a prod, looking to pull the trigger on updating my 27-inch Late 2012 2.9GHz iMac and can't decide on the 3.4GHz with 8GB RAM and the 512GB SSD or the 3.5GHz .
Main uses will be monitoring/trading stocks and shares, Betting/watching races, playing poker, light gaming (old stuff on steam Half-life and the like) and general surfing.
Is it worth getting the mid range one or do I just get the base model ? will be upgrading the RAM whichever way I go.
Cheers in advance
Paul
These threads always get hijacked. In answer to your question, for your uses it looks like the base iMac would be excellent. HOWEVER, since you kept your 2012 for six years, if you anticipate doing the same with a new iMac in three or four years you might regret not having gotten a more capable machine. If that might be the case and if you can swing the $$$ the 3.8GHz i5 model with the extra 4GB of video RAM might serve you well longer.

And we're all wondering about the spec bump. I have a week left in my 14-day return window. :)
 
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EugW

macrumors G3
Jun 18, 2017
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Thanks everyone in this thread... I'm also looking at the different specs now comparing the three i5 models, but also wondering if a spec bump is due soon anyway with WDWC.
At this point the only machine I'd consider would be a 6-core i5 (unless you get a killer deal on a quad i5).

I'm not sure if that hex-core i5 iMac will come out next week, or a few months from now.
 

karld

macrumors newbie
Mar 30, 2004
7
1
Fort Worth, TX
I also am wondering about the 3.4GHz vs 3.5 GHz iMacs. In particular, why is RAM for the 3.4 configurable to 32GB, while the for the 3.5 is configurable to 64GB? Did Apple intentionally cripple the 3.5?, or is there a difference in slots?, or a difference in the bus? Thanks. (I'm asking because my current iMac is aged out by its RAM constraint)
 

EugW

macrumors G3
Jun 18, 2017
8,423
5,792
I also am wondering about the 3.4GHz vs 3.5 GHz iMacs. In particular, why is RAM for the 3.4 configurable to 32GB, while the for the 3.5 is configurable to 64GB? Did Apple intentionally cripple the 3.5?, or is there a difference in slots?, or a difference in the bus? Thanks. (I'm asking because my current iMac is aged out by its RAM constraint)
You mean to ask about the 3.4. Typo.

It supports 64 GB but you can’t buy it with 64 GB.
 

mikehalloran

macrumors 68000
Oct 14, 2018
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The Sillie Con Valley
I don't know that there's a big difference between the i5 chips but I do know the i5 vs i7. For many users, myself included, it's huge.

If gaming, doing anything with audio of video (recording, editing etc.), spend the $200 to get an i7.

If web surfing, word processing etc. you won't notice the difference.

Intel's stock blurb is that it's 30% faster. That's nonsense. Depending on the task, it's either not noticeable or many times faster. Disk intensive tasks are the same but raw computing it's not. It just depends on the task. I've had the occasion to A/B the two many times.
 
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