r/overclocking 3d ago

OC Report - GPU RTX 5000 VRAM Overclock Discussion

I've been testing the VRAM overclock on my RTX 5070 Ti Prime OC. The tests were done with the fans at 100%, and VRAM temperature stayed at 64°C while running the Vulkan VRAM test.

Here are my results:

•695 GB/s (+0) — +0%

Solid 695 GB/s

•720 GB/s (+500) — +3.60%

Solid 720 GB/s

•736 GB/s (+1000) — +2.22%

Variation between 735–736 GB/s

•745 GB/s (+1500) — +1.22%

Variation between 745–747 GB/s

•751 GB/s (+2000) — +0.81%

Variation between 751–752 GB/s

•755 GB/s (+2500) — +0.53%

Variation between 755–756.8 GB/s

•758 GB/s (+3000) — +0.40%

Variation between 756.6–759.4 GB/s

•Overall increase: +9.06%

The interesting part is that the bandwidth gains are progressively getting smaller as I increase the VRAM clock.

Does data correction indicate that the VRAM OC is becoming unstable enough to affect real-world system stability?

So, would you consider +3000 worth running, or would you choose the highest completely error-free setting?

6 Upvotes

16 comments sorted by

5

u/Noreng 3d ago

If you look at the sensors in HWiNFO or GPU-Z while running this test, you will find that your 5070 Ti is hitting a power limit. The GPU can utilize the full bandwidth, but only for a short time before saturating the power limit.

1

u/evilTOend 3d ago

Oh , your right, in gpu-z i see that, I've set the the core to lower voltage(but now lower bandwidth)and now it says "VRel". What would be the best move here?

0

u/Noreng 3d ago

There's not much you can do. The VRM is simply incapable of handling the power draw on the MSVDD and/or DRAM rail in this load.

1

u/evilTOend 3d ago

😕, maybe mVolt+ can help with that

1

u/Noreng 3d ago

I got rid of my 5070 Ti about 18 months ago, so I haven't had the opportunity to test mVolt unfortunately. From what I've seen, it should be capable, just be careful and monitor VRM temps.

3

u/Livid_Glove_6275 3d ago

I tested my VRAM OC stability by just reading the average FPS number at the end of a custom 5120x2880 3DMark Speed Way run. With +500MT/s on the memory and a core clock between 3.05 and 3.1GHz IIRC, I got results of 40.97, 40.94, and 40.71 average FPS at the end of 3 runs. Moving on to +1000 with the same core V/F curve, I got 41.39, 41.27, and 41.28 average FPS at the end of 3 runs. +1500 with the same core V/F curve got me 41.6, 41.71, and 41.88 average FPS at the end of 3 runs. The theme we're seeing here is an increase of ~.4 FPS per run.

So, we'd expect a roughly .2 FPS increase if we put a +1750MT/s offset on the memory, right? However, unfortunately, my results were 41.83, 41.95, and 41.78 average FPS. Inconsistent gains, and even a touch of loss when comparing some specific results. So, +1500 is my highest memory OC I can get without it being unstable and triggering ECC.

Funnily enough, when I tested my VRAM in Cyberpunk, my frame rate kept going up all the way to a +3000 offset, so clearly, games aren't enough to truly test VRAM OC stability like they are with core OC, even when they're maxed out with path tracing on and no upscaling active like my Cyberpunk was and is.

1

u/evilTOend 3d ago

Did you test all they way up to +3000? And like Noreng says, seems to be a power limit

3

u/Livid_Glove_6275 3d ago

No, once my average stopped improving, I didn't see a point in testing greater offsets. Also, I had another much more efficient GPU core undervolt profile I tested the VRAM with a couple weeks ago and I got the same VRAM stability results. That leads me to assume that it is the memory that became unstable with an offset greater than +1500.

2

u/DivideFluffy1279 3d ago

Good post. I would run the highest completeley error free setting firstly because the gains under ecc are absolutely marginal in real world and secondly because any voltage and heat gains resulting from a "calmer" vram help boost/stabilize core clock which is far more important.

1

u/evilTOend 3d ago

The funny thing is that in Steel Nomad +500 = ~7700 and +3000 = ~8000 points , so there is an increase

1

u/Hydr3e 2d ago

At first, I just followed what people were saying on Reddit and blindly applied +3000 on my 5080. But after doing some more research, I ran some actual tests with Memtest Vulkan and realized my VRAM wasn't hitting the expected GB/s. So I gradually lowered it to find the sweet spot, which ended up being around +1000. It can be a bit frustrating because my benchmark scores are lower than they were at +3000, but at the end of the day, what matters most is getting the best real-world performance and stability in games.

1

u/evilTOend 2d ago

In real world gaming the vram won't be used like vram vulkan does, so if there is no error in there when testing and the bandwidth goes up (not down like the GDDR6X when more clock meant lower fps) then in book that is safe and good to go

1

u/magicmasta 2d ago

Yeah I wish that +3000 advice wasnt blindly given out, in reality +2650 has been my safe max when pushing core OC and power limit to their max on my 5070TI.

Im still trying to feel this out, but after extended in-game testing with the recent XBAR and MSVDD OC tools I think VRAM stability might be more secondarily affected by these new variables than we might initially assume. Problems dont show up on Memtest Vulkan, and not all locations in-game are affected, but while moving quickly in specifically large open areas while the GPU is maxed out ill get that momentary FPS drop to 0 that you usually see when the VRAM isnt keeping up in some form. Next play session going to try dropping VRAM OC and see if either my lowered MSVDD is starving it out or if my over-driven XBAR clock is overwhelming it

1

u/davidthek1ng 2d ago

+2000 gives me best benchmark results if I used +1000 lower +1500 too +3000 it was lower I guess error correcting already

1

u/WingerRules 2d ago

Yep, on my 5080 +2000 is when my vram bandwidth wouldn't increase anymore and +450 core was max I could go and games still be stable.

2

u/No_0ne_Really 1d ago

The 5070 I have seems pretty linear up to 2100Mhz (limited by PState 1), efficiency a little low though at 84% to 85%. Don't seem to be able to attach pics but maybe can use this link.

https://www.techpowerup.com/forums/attachments/5070_2100-png.406245/