• Welcome to our Forum! Ask PC-Build Questions, discuss Tech-News, Content Creation & Gaming Workloads or get to know the CGDirector Community off-topic. Feel free to chime in with insight or questions on any existing topic too! :)

For a second GPU, 3070 Ti or 3080 Ti ?

K

kerim

New member
Joined
Dec 22, 2020
Messages
27
Reaction score
11
Points
3
I want to buy a second GPU to improve my render times.
My first and single GPU is an RTX 3080.

On eBay (trusted sellers, buy-it-now)
the price of 3080 Ti is around 2000 USD at min.
the price of 3070 Ti is around 1200 USD at min.
So the price difference is about %66 to %70.

But what about performance difference? There are no data around yet.
What do you suggest?
Shall I go for a 3080 Ti or 3070 Ti?
Should I care about price/performance ratio, or in the long term better performance always wins?

As those prices are almost double the MSRP, if we wait till the end of summer, is it possible to buy it for more fair prices?
or the prices will continue to increase with no chance to turn back to base?

Please share your thoughts. I am very clueless about what to do.
 
Alex Glawion

Alex Glawion

CG Hardware Specialist @ CGDirector
Staff member
Joined
Jun 12, 2020
Messages
703
Reaction score
136
Points
43
GPU Prices are reported to be decreasing, especially because ethereum and bitcoin are having a difficult time right now. But you never know, they might pick up again.

A 3080Ti is almost as fast as a 3090 (give or take 1-2%) so if you don't need the 24GB of vRAM for your scenes, the 3080ti is a much better deal compared to the 3090.

The 3070Ti won't be much faster than the 3070. CUDA Cores is a good metric to look at for render performance, even if you don't have any benchmarks.

The 3070Ti has just 4% more cuda cores than the 3070. The 3080Ti has 17% more cuda cores than the 3080.

You should also beware of the cooler. Tightly packed gpus struggle with temperatures unless they are blower style.
 
K

kerim

New member
Joined
Dec 22, 2020
Messages
27
Reaction score
11
Points
3
If I am not into 8K gaming,
What is the benefit of 24GB vRAM for CGI tasks, instead of 12GB?
 
K

kerim

New member
Joined
Dec 22, 2020
Messages
27
Reaction score
11
Points
3
GPU Prices are reported to be decreasing, especially because ethereum and bitcoin are having a difficult time right now. But you never know, they might pick up again.

A 3080Ti is almost as fast as a 3090 (give or take 1-2%) so if you don't need the 24GB of vRAM for your scenes, the 3080ti is a much better deal compared to the 3090.

The 3070Ti won't be much faster than the 3070. CUDA Cores is a good metric to look at for render performance, even if you don't have any benchmarks.

The 3070Ti has just 4% more cuda cores than the 3070. The 3080Ti has 17% more cuda cores than the 3080.

You should also beware of the cooler. Tightly packed gpus struggle with temperatures unless they are blower style.
@Alex Glawion @Jerry James
Now I am considering to buy an RTX 3080 Ti or an RTX 3090 for the second GPU.
Here I attached the photo of my case.
As I see in my case, there is a nice place that would fit a second GPU just below the plugged 3080.

I am a total noob about this heat/cooler issue. So, can you please analyze if I can connect a second GPU and use it?
any GPU is OK? or blower style is a must?
 

Attachments

  • IMG_4694.jpg
    IMG_4694.jpg
    1.8 MB · Views: 11
Jerry James

Jerry James

Hardware Nerd @ CGDirector
Staff member
Joined
Jun 19, 2020
Messages
383
Reaction score
102
Points
43
@Alex Glawion @Jerry James
Now I am considering to buy an RTX 3080 Ti or an RTX 3090 for the second GPU.
Here I attached the photo of my case.
As I see in my case, there is a nice place that would fit a second GPU just below the plugged 3080.

I am a total noob about this heat/cooler issue. So, can you please analyze if I can connect a second GPU and use it?
any GPU is OK? or blower style is a must?
In general, when stacking cards for rendering, blowers are almost always the preferred choice.

1624315286679.png
Axial coolers blow out heat as shown in the diagram above. So when you start adding more than one card of this configuration, the heat build-up can get too much to handle for the case fans to push out of the case quickly enough :)

That said, for just 2 cards, you shouldn't see any noticeable performance issues as long as your case is well-ventilated with good airflow.
 
K

kerim

New member
Joined
Dec 22, 2020
Messages
27
Reaction score
11
Points
3
@Jerry James
So I am about to buy and plug a "ASUS GeForce RTX 3090 OC" to the empty place just below the first GPU, that you see in the photo I attached above.
As I understand from your last sentence, it will be okay :)
 
Jerry James

Jerry James

Hardware Nerd @ CGDirector
Staff member
Joined
Jun 19, 2020
Messages
383
Reaction score
102
Points
43
@Jerry James
So I am about to buy and plug a "ASUS GeForce RTX 3090 OC" to the empty place just below the first GPU, that you see in the photo I attached above.
As I understand from your last sentence, it will be okay :)
Add more front intake fans to your case (total of 3 if possible) to ensure there's enough airflow.
 
Alex Glawion

Alex Glawion

CG Hardware Specialist @ CGDirector
Staff member
Joined
Jun 12, 2020
Messages
703
Reaction score
136
Points
43
Beware that most render engines will use the gpu with the smallest vram capacity as the default common denominator. This means even though the 3090 has 24gb, your rendering will be limited by the 10gb of vram on the 3080.

To circumvent this you'll have to render multiple frames at once, with each gpu rendering its own frame. Rendering on just one frame with both gpus, will limit the vram. You can use rendermanagers such as thinkbox deadline for this.

If your scene easily fits into 10gb of vram you won't have any slowdowns. Just when the scene is too big for the 3080.
 
  • Like
Reactions: kerim and Jerry James
K

kerim

New member
Joined
Dec 22, 2020
Messages
27
Reaction score
11
Points
3
I ended up buying an EVGA RTX 3080 Ti FTW3 as the second GPU.
So as @Jerry James 's advice, I am planning to purchase extra case fans. I did some more researches to come up with a configuration. But I would like to represent it to you to give the final decision, and I am in between two case-fan models. @Alex Glawion
Here I attached an image to show the configuration.
Two fans will be attached to the top of the case (140 MM PMW - Exhaust).
Two fans will be attached to the front of the case (140 MM PMW - Intake).
** As I understand, same fan can be used as either exhaust or intake. The rotation is defining that function.
What is your final opinion about that configuration?

And, now in Turkey, what I can find available in local stocks are:
Be Quiet! SILENT WINGS 3 140mm PWM
and
NOCTUA NF-P14s redux-1500 PWM
They are almost the same price.

Be Quiet! is offering 1000 RPM and 101 m3/h airflow, with a maximum of 15.5 dB(A).

NOCTUA is offering 1500 RPM and 133 m3/h airflow, with a maximum of 25,8 dB(A).

In short, Be Quiet! is very quiet. And NOCTUA is powerful.

Which one would you suggest for my scenario?
Of course, I would like to go with the silent one but, is the performance difference that NOCTUA offers is important?
Is the sound difference between 15.5 dB(A) and 25,6 dB(A) very noticeable for four pieces of fans?
 

Attachments

  • Case-Fans.jpg
    Case-Fans.jpg
    4.1 MB · Views: 10
Alex Glawion

Alex Glawion

CG Hardware Specialist @ CGDirector
Staff member
Joined
Jun 12, 2020
Messages
703
Reaction score
136
Points
43
The two GPUs' fans will almost certainly be much louder than all case fans combined during rendering, so both 15 or 25 db is not something to be concerned about. That said, with my limited case-fan knowledge, I'd say the outgoing fans should be stronger so you can create negative pressure inside the case, which'll also help with intake at the front. The two front fans can be the bequiet.
 
  • Like
Reactions: Jerry James
K

kerim

New member
Joined
Dec 22, 2020
Messages
27
Reaction score
11
Points
3
Thanks a million @Alex Glawion @Jerry James !
Less than a year ago, I was a Mac guy and have zero knowledge about the hardware ecosystem.
Now I feel like I am becoming a cable guy and I kinda like it :)
 
  • Like
Reactions: Jerry James and Alex Glawion
Jerry James

Jerry James

Hardware Nerd @ CGDirector
Staff member
Joined
Jun 19, 2020
Messages
383
Reaction score
102
Points
43
I ended up buying an EVGA RTX 3080 Ti FTW3 as the second GPU.
So as @Jerry James 's advice, I am planning to purchase extra case fans. I did some more researches to come up with a configuration. But I would like to represent it to you to give the final decision, and I am in between two case-fan models. @Alex Glawion
Here I attached an image to show the configuration.
Two fans will be attached to the top of the case (140 MM PMW - Exhaust).
Two fans will be attached to the front of the case (140 MM PMW - Intake).
** As I understand, same fan can be used as either exhaust or intake. The rotation is defining that function.
What is your final opinion about that configuration?

And, now in Turkey, what I can find available in local stocks are:
Be Quiet! SILENT WINGS 3 140mm PWM
and
NOCTUA NF-P14s redux-1500 PWM
They are almost the same price.

Be Quiet! is offering 1000 RPM and 101 m3/h airflow, with a maximum of 15.5 dB(A).

NOCTUA is offering 1500 RPM and 133 m3/h airflow, with a maximum of 25,8 dB(A).

In short, Be Quiet! is very quiet. And NOCTUA is powerful.

Which one would you suggest for my scenario?
Of course, I would like to go with the silent one but, is the performance difference that NOCTUA offers is important?
Is the sound difference between 15.5 dB(A) and 25,6 dB(A) very noticeable for four pieces of fans?
Looks great to me overall. As Alex said, get the static pressure Noctuas to push air (for your exhaust). One thing that looks slightly pointless is that first (from the front of the case) top exhaust. It looks like it'll end up exhausting that top intake almost immediately, effectively doing nothing.
 
Top