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Tucom

Cancelled
Jul 29, 2006
1,252
310
The watt numbers I reported were measured externally with a Kill a Watt, so measured the total system power use of the iMac. So 175 watts while the GPU is being pushed hard includes the GPU, screen, some CPU, and other components. At least 35-40 watts are being used by those other parts, so the upper limit of the GPU would be 135-140. That assumes that the GPU was really pushed to the max, and considering the temperatures and fan speed, I think it was.

Aside from that, I'm pretty sure that the linked article just had their facts wrong. 250 watts is the rating for the desktop equivalent. It would make no sense that the mobile chip would have the same rating. I can't put my hands on the sources at the moment, but I've seen reports that puts the m295x at 125 watts. In the end it doesn't really matter. The system is limited by how much cooling can be done. It's pretty clear that the upper limit for heat output for the GPU is about 105 C., and the fan and possible throttling don't let it go higher. AMD obviously thinks thats not too high.

Apple indicates the M295X riMac can pull up to 288 watts, and that's "CPU Max" - not sure if they're including the GPU and display, as well.

http://support.apple.com/en-us/HT201918
 

joema2

macrumors 68000
Sep 3, 2013
1,645
864
Apple indicates the M295X riMac can pull up to 288 watts, and that's "CPU Max" - not sure if they're including the GPU and display, as well.

http://support.apple.com/en-us/HT201918

That is everything -- CPU, GPU, display, all other support circuitry, etc. By "CPU Max" they mean maximum possible CPU/GPU consumption, not just max stand-alone CPU consumption.

The statements and web site stating 250w TDP for the M295X are in error. They got it mixed up with the desktop R9 series. Whoever originally made the error may have taken the R9 295X2 (500w TDP) and just divided by two, thinking the M295X was half of that. I don't know what the M295X TDP is but it can't be hugely over 100w.
 
I had a very difficult time reading the original question in this thread due to the lack of punctuation/run-on sentence. I nearly gave up on and pressed on, but I finally made it through.

What Gary has shared with you is very good advice. In my opinion, an upgraded GPU is almost more important than an upgraded CPU. Several years down the road, the first thing to bring a computer to its knees will be the GPU. I think it is best to upgrade it now, especially in an all-in-one computer such as the iMac.

Cheers,
Bryan


Brian, you made an excellent point.

My poor rmbp late 2013, hooked up to a Dell ultras sharp 27" IPS display is really struggling. I often max out the ram with my current usage: safari, chrome, Vm, PowerPoint, word, Adobe all running. I often have to force quit and restart if I decide to play even a modest graphic intensive game - ie simcity . My point bring, that although yosemite has been an excellent update, I can fell my needs out strip the power my poor Intel integrated GPU can provide. I was going to buy the rImac, but have decided (quite foolishly) to bear with my current setup, until the next refresh is released (hoping for skylake, tb3, hdmi 2+, USB 3.1, nvidia graphics and the return of target display mode- I fear this may be wishful thinking!)
 

joema2

macrumors 68000
Sep 3, 2013
1,645
864
...Wait for SKYLAKE or buy the 5K Haswell iMac now...

I just saw this today on Skylake. Apparently the Quick Sync on-chip transcoder will be enhanced for several additional codecs. For video editors this is a powerful, compelling feature.

http://www.cpu-world.com/news_2014/2014060901_Some_features_of_Skylake_graphics_architecture.html

"Skylake integrated video encoder/decoder will be enhanced, and it will support new codec types. The hardware decoder will work with JPEG, JMPEG, MPEG2, VC1, WMV9, AVC, H264, VP8 and HEVC/H265 video and image formats. The encoder will be support JPEG, MPEG2, AVC, H264, VP8 and HEVC/H265 standards. It is possible that Intel will add support for encoding/decoding of VP9 video. "
 

Crunch

macrumors 6502a
Jun 26, 2008
701
76
Crazy L.A.
(...) It's extremely unlikely that you will see difference in 2D performance between the M290X and M295X. (...)

The M295X is only need if you're gaming, doing 3D stuff, or doing video editing.

Really? Then why do so many machines (including my own) equipped with only the base model (the 290X) have such horrible lag??? Something as seemingly innocuous as Mission Control or browsing graphics-laden sites in Safari was so time-consuming and irritating that I returned it and re-purchased the 295X upgrade.

Ever since I've received the new model, all lag is just gone! I love it! The base model caused me nothing but problems.
 

librarian

macrumors regular
Sep 24, 2011
107
3
main problem of both cards is their limited amount of VRAM for 5k resolution. Given that yosemite use about 1,5gb of the 2 GB pool after booting no wonder it lags like hell with m290x.
 

Crunch

macrumors 6502a
Jun 26, 2008
701
76
Crazy L.A.
main problem of both cards is their limited amount of VRAM for 5k resolution. Given that yosemite use about 1,5gb of the 2 GB pool after booting no wonder it lags like hell with m290x.

Which app are you using to measure the VRAM usage in the 290X? I'm using iStat Menus (Windows not installed yet) and it appears that more than half is taken up by the 295X. This would mean over 2GB, as the 295X has 4GB of VRAM. With browser tabs and other apps open, it looks like the 295X is using nearly ALL of its VRAM.

I'm not sure how reliable the iStat way of measuring things are when it comes to this bleeding-edge chip, the 295X. To date, you can't find much about it elsewhere because it's so new. Might this be an issue with iStat?
 

JDW

macrumors 6502
Jul 12, 2005
337
249
Japan
...why do so many machines (including my own) equipped with only the base model (the 290X) have such horrible lag???
Ever since I've received the new [295X upgrade] model, all lag is just gone! I love it! The base model caused me nothing but problems.

Assuming the "base model" had everything (RAM/SSD/CPU/etc.) exactly the same as the "295X model," with the only difference being the GPU chip, then your experience should trounce all "speculation" posted in this thread.

But I still wish someone out there would shoot us some video. Shoot some video of that lag. Then when you get your new "upgraded GPU" model, shoot video of the same apps in the same situations showing us how there is no more lag. That would be the nail in the coffin on this GPU issue.
 

ra004e

macrumors regular
Jun 8, 2009
143
21
Assuming the "base model" had everything (RAM/SSD/CPU/etc.) exactly the same as the "295X model," with the only difference being the GPU chip, then your experience should trounce all "speculation" posted in this thread.

But I still wish someone out there would shoot us some video. Shoot some video of that lag. Then when you get your new "upgraded GPU" model, shoot video of the same apps in the same situations showing us how there is no more lag. That would be the nail in the coffin on this GPU issue.

I have base unit and additional 4k monitor hooked up with no lag as long as the System Preferences > Accessibility > Increase Contrast is selected. I had a M295X unit before this one and it would lag as well once enough windows were opened. I do believe the M295X is the superior chip, but something with the transparency in Yosemite UI seems to be causing the additional stress for M290X. After speaking with Apple 2nd level support, they were convinced this is a software issue and would be eventually resolved. We'll see.

Anyway, anyone with base GFX should see if they can live without UI transparency ( System Preferences > Accessibility > Increase Contrast is selected ) as the system is way more responsive and lag at least for me has not been an issue. Try selecting System Preferences > General > Use dark menu bar and Dock and Appearance = Graphite, as might mitigate the feel of losing transparency somewhat ( my opinion ).
 
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Crunch

macrumors 6502a
Jun 26, 2008
701
76
Crazy L.A.
Assuming the "base model" had everything (RAM/SSD/CPU/etc.) exactly the same as the "295X model," with the only difference being the GPU chip, then your experience should trounce all "speculation" posted in this thread.

But I still wish someone out there would shoot us some video. Shoot some video of that lag. Then when you get your new "upgraded GPU" model, shoot video of the same apps in the same situations showing us how there is no more lag. That would be the nail in the coffin on this GPU issue.

Yes, my new Retina iMac with the 295X has precisely the same specs, and I'm running exactly the same apps, same amount of RAM, same CPU (the i5 3.5GHz), same SSD w/ no hard drive, and the difference is night and day. And yes, you're right. I should've taken some video of my base model iMac that had the 290X in it.


I have base unit and additional 4k monitor hooked up with no lag as long as the System Preferences > Accessibility > Increase Contrast is selected. I had a M295X unit before this one and it would lag as well once enough windows were opened. I do believe the M295X is the superior chip, but something with the transparency in Yosemite UI seems to be causing the additional stress for M290X. After speaking with Apple 2nd level support, they were convinced this is a software issue and would be eventually resolved. We'll see.

Don't bet on it. Sounds like they're passing the buck. The 290X is simply underpowered. It's crazy that you can't do basic stuff without constant lagging without having to plunk down another $250 for an upgraded part. Who can work like that?

I had called Apple as well, by the way, and they kept transferring me around until someone eventually hung up on me. What a joke. They tried to have me believe that a software fix was coming as well. Yea, right. You mean the fix that won't fix anything will come right around the time the return window closes? Hah.
 

cynics

macrumors G4
Jan 8, 2012
11,959
2,154
Yes, my new Retina iMac with the 295X has precisely the same specs, and I'm running exactly the same apps, same amount of RAM, same CPU (the i5 3.5GHz), same SSD w/ no hard drive, and the difference is night and day. And yes, you're right. I should've taken some video of my base model iMac that had the 290X in it.




Don't bet on it. Sounds like they're passing the buck. The 290X is simply underpowered. It's crazy that you can't do basic stuff without constant lagging without having to plunk down another $250 for an upgraded part. Who can work like that?

I had called Apple as well, by the way, and they kept transferring me around until someone eventually hung up on me. What a joke. They tried to have me believe that a software fix was coming as well. Yea, right. You mean the fix that won't fix anything will come right around the time the return window closes? Hah.

UI lag should be able to be fixed with software, whether it is or not is a different question. Its a relatively mundane task causing the lag. Plus, less powerful Apple hardware running 4k displays can do so without much issue.

If you can run a highly optimized game at 1440p at a decent FPS. But can't open Mission Control or something without lag is a pretty good indicator of where the issue lies.

I don't know what the common dominator is but I haven't seen any noticeable lag on my buddies i7/m290x 5k iMac. However I don't use it day in and day out so my observation is relatively meaningless. I'd like to see a video of it so I could try to recreate it (maybe one was posted so I missed it?).
 

JDW

macrumors 6502
Jul 12, 2005
337
249
Japan
While contemplating this thread, I must say this. If Retina MacBook Pro users sporting s M290 or M295 are experiencing a noticeable "LAG," then MacBook AIR users must really be hating life!
 

grame

macrumors member
Nov 12, 2007
89
0
My 290 is fine when I disable the reduced transparency function. Prefer it that way anyway,
 

FrozenDarkness

macrumors 68000
Mar 21, 2009
1,727
968
My 290 is fine when I disable the reduced transparency function. Prefer it that way anyway,

turning off transparency is like the first thing thye tell you to do to speed up your mac. i turned it off my rmbp 13" and everything is smooth as ice.

except safari still sucks on yosemite
 

JDW

macrumors 6502
Jul 12, 2005
337
249
Japan
Speaking of "turning things off"...

http://appleinsider.com/articles/15...t-expands-accuses-apple-of-concealing-defects

"...reduced the graphical performance of the GPUs in order to prevent them from reaching temperatures that would cause the GPUs to effectively self destruct..."

Even though Apple probably learned a lot from its 2011 designs, it's still probably SAFER to switch off transparency to go easier on the GPU chip.

Heat kills.
 

clayj

macrumors 604
Jan 14, 2005
7,617
955
visiting from downstream
So...

... is there a consensus as to whether the M290x is acceptable for someone who just runs Safari, Mail, and VMware Fusion (with Windows 8.x) and doesn't use the iMac at all for gaming or video editing? I'm *thisclose* to pulling the trigger on a Retina iMac, but dropping an extra $250 for an upgraded GPU that might cause heat issues is a worrisome point.
 

andy9l

macrumors 68000
Aug 31, 2009
1,699
365
England, UK
AMD Radeon R9 M290x vs M295X

... is there a consensus as to whether the M290x is acceptable for someone who just runs Safari, Mail, and VMware Fusion (with Windows 8.x) and doesn't use the iMac at all for gaming or video editing? I'm *thisclose* to pulling the trigger on a Retina iMac, but dropping an extra $250 for an upgraded GPU that might cause heat issues is a worrisome point.


The M295X is clearly the more powerful GPU. The downside to it is that you only get the maximum power for a minute or two before it throttles itself in order to, once again, avoid self-destructing. An AMD/Apple speciality, it seems.

I returned my i7/M295X 5K iMac partly based on my fundamental disagreement with that compromise. I did not want to pay for something I don't really get because of, one can only assume, design negligence.

However, I assume you will be buying Apple Care with this Mac, so you're covered even if it does cause damage.

On the other hand, if a $2,500 computer (M290X) cannot achieve the basic tasks you've posted, I would argue that puts a real question mark over the price tag - 5K screen or no 5K screen.

To give you a direct answer; yes the M290X should be good enough. It will lag, but that will improve with software refinements, I'm sure. The M295X is bloomin' hot, but you're covered with Apple Care anyway. You will get better performance, but more fan noise with the M295X.
 

clayj

macrumors 604
Jan 14, 2005
7,617
955
visiting from downstream
The M295X is clearly the more powerful GPU. The downside to it is that you only get the maximum power for a minute or two before it throttles itself in order to, once again, avoid self-destructing. An AMD/Apple speciality, it seems.

I returned my i7/M295X 5K iMac partly based on my fundamental disagreement with that compromise. I did not want to pay for something I don't really get because of, one can only assume, design negligence.

However, I assume you will be buying Apple Care with this Mac, so you're covered even if it does cause damage.

On the other hand, if a $2,500 computer (M290X) cannot achieve the basic tasks you've posted, I would argue that puts a real question mark over the price tag - 5K screen or no 5K screen.

To give you a direct answer; yes the M290X should be good enough. It will lag, but that will improve with software refinements, I'm sure. The M295X is bloomin' hot, but you're covered with Apple Care anyway. You will get better performance, but more fan noise with the M295X.
Hrm. So the choices are:

  • M290X which may not run as smoothly as one would like when performing even basic windowing tasks. (FWIW, my plan was to spec the 4 GHz i7 with 256 GB SSD, and then add RAM to jump to 32 GB and external Thunderbolt storage.)
  • Or, M295X which acts like an afterburner, giving short boosts to performance while causing the entire machine to overheat and potentially shorten its lifespan.
It almost sounds like Apple have, at least for now, bitten off more than they can chew with the 5K screen -- they've got the pixels, but can't drive them properly and safely no matter which GPU you go with.

As far as AppleCare goes: I wasn't planning to buy that. I did that with my 2008 Mac Pro and nothing ever happened to the machine in 7 years.
 

richard371

macrumors 68040
Feb 1, 2008
3,605
1,802
I have the 295X, I7 SSD and have no issues with heat. I don't play games but run VMware, PS, LR, iMovie. I think its worth the 4GB VRAM alone. I played xplane 10 a bit and sky gamblers and it did heat up a bit but nothing to concern me. $119 for 3 year Apple care (student) is a no brainer on a 3K plus machine. Ill probably sell it for the newer model in 2.5 to 3 years so I am covered.

... is there a consensus as to whether the M290x is acceptable for someone who just runs Safari, Mail, and VMware Fusion (with Windows 8.x) and doesn't use the iMac at all for gaming or video editing? I'm *thisclose* to pulling the trigger on a Retina iMac, but dropping an extra $250 for an upgraded GPU that might cause heat issues is a worrisome point.
 

JDW

macrumors 6502
Jul 12, 2005
337
249
Japan
As far as AppleCare goes: I wasn't planning to buy that. I did that with my 2008 Mac Pro and nothing ever happened to the machine in 7 years.

A Mac Pro is a very different beast than an iMac. Do NOT compare the two. A lot more stuff is crammed into a less-cooled case when you have an iMac.

I had AppleCare on my Nov. 2009 iMac. About 3 years later, just when the AppleCare expired, the video chip(s) died. Why? Heat.

All said, make well-informed, well-thought-out decisions when configuring an iMac. It would be better to buy a Mac Pro, but it just costs too much for those of use who aren't the "pros" Apple designed it for. Furthermore, the iMac is FASTER in many situations than the Pro.
 

andy9l

macrumors 68000
Aug 31, 2009
1,699
365
England, UK
AMD Radeon R9 M290x vs M295X

Hrm. So the choices are:



  • M290X which may not run as smoothly as one would like when performing even basic windowing tasks. (FWIW, my plan was to spec the 4 GHz i7 with 256 GB SSD, and then add RAM to jump to 32 GB and external Thunderbolt storage.)
  • Or, M295X which acts like an afterburner, giving short boosts to performance while causing the entire machine to overheat and potentially shorten its lifespan.

It almost sounds like Apple have, at least for now, bitten off more than they can chew with the 5K screen -- they've got the pixels, but can't drive them properly and safely no matter which GPU you go with.



As far as AppleCare goes: I wasn't planning to buy that. I did that with my 2008 Mac Pro and nothing ever happened to the machine in 7 years.


For what you do, the i7 and 32GB of RAM will be wasted. 8GB RAM would be more than enough, and 16GB would be a very safe overkill. You need to be doing some serious, serious work to utilise 32GB. Free RAM is wasted RAM and low 'free RAM' in activity monitor is not an indication of you needing more, rather 'memory pressure' should be analysed. As for the i7, you don't do any tasks that heavily utilise multi-threading - so you won't benefit much at all from the processor.

I do feel as though you're exaggerating the M295X issues, though. It's hot, sure, but it never caused my 5K iMac to overheat. In fact, I have never seen a report of that. The i7 CPU and M295X inside a 5K iMac will throttle under load (around 10-15%) to avoid overheating. This is heavily analysed online, on tech blogs, on YouTube, the lot. It is not the same as overheating the entire iMac.

I don't think they have bitten off more than they can chew, they have put some of the best hardware available into this iMac, but I believe they neglected to invest in a new product design to support that hardware this time round. I would be extremely surprised if the next 5K iMac didn't have a new physical design. The reason for omitting it this time round may have been due to profit margins already suffering due to the 'cheap' price of this iMac, given the 5K screen. With Apple, EVERYTHING is about profits.

Please, please invest in AppleCare. Save money on the unnecessary RAM and spend it on this instead. You're buying a first-gen product with AMD GPUs in again. The AMD mobile GPUs Apple used in 2011 put the entire range (iMac and MacBook) in lawsuits, recalls, the full works. The past is not necessarily an indication of the future, but it provides some doubts given the immediate and widespread concerns over heat and relatively poor performance.

I realise I'm not helping with your choice, but I'm just relaying everything I've researched over the past 3 months or so.

For you I would not hesitate to recommend the i5/M290X 5K iMac with the 256/512GB SSD. Upgrade to 16GB of RAM yourself if you really need it for the VM. It will be more than capable of achieving the tasks you've stated. The screen is absolutely brilliant on these machines, and the hardware provides good mid-range performance for professional work, as you'd expect from an iMac.
 
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JDW

macrumors 6502
Jul 12, 2005
337
249
Japan
If I were buying a Mac Pro, I probably won't worry about AppleCare. (That remains true even if I had enough money to buy a Mac Pro -- yes, I am THAT cheap!) But with an iMac, knowing first hand the heat issues, I would definitely buy AppleCare even though it hurts my wallet. What if an issue crops up just after the 3 year mark? Do like I did and write Tim Cook. Despite the fact my AppleCare had just expired, he referred me to an Apple exec who offered me a free fix. Yes, Apple has great support. Don't expect this in every case, but I just mentioned it because it happened to me.

For me, the solution to the GPU choice dilemma is to WAIT until the next-gen Retina iMac comes out. Who knows, it might offer a SKYLAKE CPU too, and with that CPU come some real improvements in other areas too.

Don't listen to folks who say, "just buy the machine you need right now." Waiting is NOT a "never-ending proposition" to those of us who intelligently shop. Disclaimer: I was stung once with a Mac IIvx purchase in the past. For those of you old enough to know what that means, you can appreciate the benefits of waiting just a tad longer before pulling the trigger on a computer purchase. There will always be something better, to be sure. But you should only buy when your gut tells you too, not due to pressure from peers in an online forum. Sure, the current Retina iMac seems great, but the next edition will probably be a bit better in the graphics department. Think about the first-gen Retina MacBook Pro versus what we have now.

As to RAM, don't listen to people who say "8GB is enough." I use my iMac at home, and I have a wife. She has her own user account. And she leaves her browser windows open, AND she has many tabs! One day when I had 8GB, I found my iMac slowing to a crawl. After much investigation, I found it was due to lack of RAM. I bought 16GB and now I am in wonderland! It's great. Not sure if I need 32GB at this time, but if I ever do buy a new iMac, I will buy 32GB. Why? Because I am Mr. El Cheapo who doesn't upgrade an iMac but once in a blue moon. Seriously, six or seven years is not unusual for me. I can't imagine I am alone either.

Best wishes.
 

andy9l

macrumors 68000
Aug 31, 2009
1,699
365
England, UK
Just to be clear, 8GB of RAM WILL be enough for your usage. Unless you're doing something serious in the VM.

Apple still sell brand new MacBook Airs with 4GB. According to JDW's logic, those Macs will be unusably slow from day one. I beg to differ.

If I'm wrong, you only need to spend $50 and 60 seconds of your time installing more.
 
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