http://www.techpowerup.com/209205/geforce-gtx-970-design-flaw-caps-video-memory-usage-to-3-3-gb-report.html#comments

According to Nvidia, this is by design. Not sure about this.

 

http://www.pcper.com/news/Graphics-Cards/NVIDIA-Responds-GTX-970-35GB-Memory-Issue

It appears as if this is not a flaw but a poor design choice by Nvidia compounded by them being economical with the facts on launching the card. Apparently the 4Gb of memory is split into 2 sections, one larger 3.5Gb section and a smaller 0.5Gb section. In situations where the card needs to use all of the available 4Gb then performance is noticeably degraded because of the way the 2 sections of memory have to interact with each other. This only appears to be an issue with a small number of games that utilise high memory levels or when using very high screen resolutions (1440p +) resulting in in-game stutters. Some online resellers and card manufacturers are now allowing returns on 970s because of this issue and the fact that the original OEM specifications published were not factually correct.

 

Because of this I'm expecting that resale values of 970s will take a hit especially with fully functional 'B' grade items that have been returned due to their owners choosing to replace these cards with an alternative that does not suffer with this issue, and second hand values will most likely take a massive hit.

 

Cutting to the chase I was wandering if 970 owners have experienced any such issues with FSX especially with DX10 as I'm thinking for my needs a low cost 970 might be a worthy upgrade to my current 680 which I use mostly for FSX.

The 660 has a similar configuration (practically, if not functionally), but in it's perf segment I guess it never really became much of an issue.

 

It has been an interesting week of reading for sure. I do believe that even with the correct specs/info up front, the card would still have sold quite well. The folks I truly feel for are those that side-graded from 780 specifically for the extra VRAM, and of course, anyone that went SLI for 1440p-4K.

 

It still is an excellent card even with the caveats, it's just difficult to understand how/why nv let it get to this point in the first place. If FSX/P3D is your primary concern then the 970 is still a great choice, it's just unfortunate that the details weren't disclosed upfront.

I don't think it was a poor design choice. It's the expected behavior and a trade-off the engineers at Nvidia made. It's extremely unfortunate that this wasn't communicated to the marketing team. The big issue is obviously not the configuration of the GPU (it's a lower-tier GPU than the 980, there are supposed to be trade-offs), but that Nvidia, deliberately or not, misled customers and publications. This is why Nvidia and its partners should absolutely offer refunds/returns.

 

The GTX 970 still looks like a great GPU. This discovery does not affect the published benchmark results or previous user experiences. People will of course now blame their GTX 970's for all kinds of stutters and low framerates, even when VRAM usage isn't actually close to the 3.5GB threshold. This can be great news for those looking to upgrade from older cards, as prices should go down and more GTX 970's should become available in the second-hand market.

I don't think it was a poor design choice. It's the expected behavior and a trade-off the engineers at Nvidia made. It's extremely unfortunate that this wasn't communicated to the marketing team. The big issue is obviously not the configuration of the GPU (it's a lower-tier GPU than the 980, there are supposed to be trade-offs), but that Nvidia, deliberately or not, misled customers and publications. This is why Nvidia and its partners should absolutely offer refunds/returns.

 

The GTX 970 still looks like a great GPU. This discovery does not affect the published benchmark results or previous user experiences. People will of course now blame their GTX 970's for all kinds of stutters and low framerates, even when VRAM usage isn't actually close to the 3.5GB threshold. This can be great news for those looking to upgrade from older cards, as prices should go down and more GTX 970's should become available in the second-hand market.

+1

The Guru3D article about the subject:

 

http://www.guru3d.com/news-story/does-the-geforce-gtx-970-have-a-memory-allocation-bug.html

 

Excerpt: "On a generic notice, I've been using and comparing games with both a 970 and 980 today, and quite honestly I can not really reproduce stutters or weird issues other then the normal stuff once you run out of graphics memory. Once you run out of ~3.5 GB memory or on the ~4GB GTX 980 slowdowns or weird behavior can occur, but that goes with any graphics card that runs out of video memory. I've seen 4GB graphics usage with COD, 3.6 GB with Shadows of Mordor with wide varying settings, and simply can not reproduce significant enough anomalies".

 

GTX 970 VRAM stress test

 

http://www.guru3d.com/news-story/middle-earth-shadow-of-mordor-geforce-gtx-970-vram-stress-test.html

http://www.anandtech.com/show/8935/geforce-gtx-970-correcting-the-specs-exploring-memory-allocation

So how much memory does my 970 use with BP=0?

 

Does it approach 4gb?

So how much memory does my 970 use with BP=0?

 

Does it approach 4gb?

 

A tool like MSI's Afterburner will run in the background and allow you to monitor and chart memory and GPU usage whilst running FSX. I'd be interested to know your results if you'd care to post them along with what screen resolution you are running at.