Graphics Nvidia’s GTX970 has a rather serious memory allocation bug

That is a 64 page thread, the first page did not appear to have an Nvidia rep confirming the issue. Could you be more specific? Some of us are browsing without a working mouse, you know.

 

I was on the GameFAQs PC forum a bit recently (whose inhabitants I rank only slightly lower than the Steam forums on the PC Elitist scale) and they were recommending everyone the 970, no matter what the parameters. "970, 970, get the 970, I'm getting the 970, 970 is all you need, future-proof, 970, 970, 970".

So I knew something was going to go wrong.

 

it appears that its related to HYNIX memory modules as the SAMSUNG ones appear to be working as intended.

edit:

http://www.reddit.com/r/pcmasterrac...ia_is_ignoring_any_forum_posts_about_low_gpu/

microstuttering on single GTX 970

 

From what i can tell nothing has gone wrong, everything i have read says that the 970 prefers to use 3.5GB ram and when it does use all of its 4GB the performance impact is negligible (1-3%)

The only things i have found to the contrary have been posted by the same type of ill-informed people that posted screenshots of a benchmark. TweakGuides.com has posted what their findings are if anyone is interested, but i think the most salient point is...

 

Tested with Far Cry @ 4k res. MSI Kombustor etc. Everything is smooth here... no hitching or pausing when going over 3.5GB

 

Don't know what all the fuss is about, this is on my Asus 970 Strix SLI rig.

Far Cry 4 @ 4k ultra with 2xTXAA using 3.6GB of VRAM







..and with 4xTXAA using 3.8GB of VRAM



The performance drop is perfectly in line with using such extreme settings, that and the fact Ubisoft can't code a decent graphics engine on the PC to save their lives.

EDIT:

Also don't have any problems running Battlefield 4 when it peaks at something like 3.75GB VRAM @4k, get a consistent smooth 50-60fps.

So again, what's all the fuss about?

 

At this point, a whole bunch of people with any sort of issue with a GTX 970 are declaring that it's entirely due to vRAM. There are plenty of forum threads filled with anecdotes of "I get stuttering, and it's totally due to using more than 3.5GB (and nothing at all to do with rendering at 4k DSR or using extreme texture sizes or turning up AA to 16x or turning all the shader effects to ultra)". None of these actually provide any numbers, and none of them do any further testing to determine if the performance drop is caused by vRAM access speed, or simply because turning up various setting puts a lot of demand on the entire GPU anyway.

 

Hustler - what ram make is on your card?

 

MSI Kombustor is interesting.

Using GPU memory burner and 2560x1600, 8xMSAA

I get.

1024MB = 73fps
2048MB = 61fps
3072MB = 31fps

In actuality, that last one is using 3700MB

Can someone with a 980 please confirm the disparity? If the 980 also displays a severe drop off at the higher memory setting, I'm happy with my card. If it doesn't, I'm not.

Simple as that really, as the card seems to have no issue accessing the extra RAM beyond 3.5GB.. and if the 980 also suffers a similar proportionate frame rate drop, then I'm assuming my card is behaving normally.

 

Hynix ram on your card?

 

Even if a 980 didn't see the same drop in performance how would you know it's not caused by the other differences between the two ?

 

Hi is there a program to check ram manufacturer of do you need to physically check your self

 

GPU-Z will tell you

 

Yes thankyou i never noticed mine has samsung in my msi's

i cant run msicombuster though @3gb it crashes or halts my system in sli or without sli

 

My EVGA SC ACX 2.0 is said to be Samsung according to GPU-z. Pookey said he's got the same.card.

 

So looking at that, the extreme settings chugging on certain games could be because the last 500MB has an issue, contrary to the popular line: "what do you expect with 8xMSAA + 4k, you should expect framerates in the minus and a western civilization apocalypse"... etc.

 

Well.. the contentious issue is the splitting of the RAM, so if the 980 exhibits the same drop in frame rate in Kombustor, then the frame drop is not caused by that. That would satisfy me that it's behaving as it should.

Samsung RAM.

Which is why getting someone with a 980 to run the same test would answer the question. If THEY get a similar drop in performance, then it;'s nothing to do wit the RAM splitting thing.

 

This morning NVidia has released a statement on the matter, which AnandTech republishing in full:

The GeForce GTX 970 is equipped with 4GB of dedicated graphics memory. However the 970 has a different configuration of SMs than the 980, and fewer crossbar resources to the memory system. To optimally manage memory traffic in this configuration, we segment graphics memory into a 3.5GB section and a 0.5GB section. The GPU has higher priority access to the 3.5GB section. When a game needs less than 3.5GB of video memory per draw command then it will only access the first partition, and 3rd party applications that measure memory usage will report 3.5GB of memory in use on GTX 970, but may report more for GTX 980 if there is more memory used by other commands. When a game requires more than 3.5GB of memory then we use both segments.

 

I'm inclined to agree. So far I've seen nothing to make me suspect the card is anything other than brilliant. I'm just watching developments carefully.

I would still implore anyone reading this thread who has a 980 to run the Kombustor GPU memory burner tests as I feel that would shed some light on the issue.

 

As a flip side - more users are reporting micro stuttering on 4k displays....a possible sign of the issue?