Bottleneck concerns

[Javed shamim]

Currently I have

3770k at 4.5Ghz

ROG Maximus V formula

16gb 2400mhz gskill trident x ram

2x r9 290

I would like to add another r9 290

So I can run trifire with 3x 1080p monitors.

My concern is would I be getting a Cpu bottleneck with 3 cards ?

And the motherboard will run 3 cards in 8x/4x/4x.

Will the two cards running at 4x speeds downgrade performance noticeably?

I mainly play BF4, titanfall , crysis 3,etc

Thanks in advance

[LIGISTX]

All I know for sure is the CPU will be fine, 4.5 GHz is plenty. But, 4x I am not sure about, and would be slightly worried about. I know nvidia doesn't let SLI work on 4x, and I have tried an oldish GPU as a PhysX card in a 4x slot and it did so crappy I couldn't even believe it. I wouldn't do 4x.

[Askew]

So you are unhappy with the performance of 2 cards?

 

If you have PCIE 3.0 enabled then those 4x slots are equivalent to 2.0 8x slots and I remember 2 way GPU in 8x8 on 2.0 being reported not to make a difference when the GTX 780 came out.

 

But 3 way + was reported to have issues, also your cards do communicate with each other more than previous generations through the PCIE bus now (connectorless Xfire).

 

I wouldn't do it personally, but someone might be able to give better advice.

[LawrenceBarnes2013]

if it was a pentium or a dual core, yes yes you should be concerned, but a 3770K, 4Cores, come on man ! no bottleneck to be caused mate, you're good to go

[Faa]

Currently I have

3770k at 4.5Ghz

ROG Maximus V formula

16gb 2400mhz gskill trident x ram

2x r9 290

I would like to add another r9 290

So I can run trifire with 3x 1080p monitors.

My concern is would I be getting a Cpu bottleneck with 3 cards ?

And the motherboard will run 3 cards in 8x/4x/4x.

Will the two cards running at 4x speeds downgrade performance noticeably?

I mainly play BF4, titanfall , crysis 3,etc

Thanks in advance

Don't add a 3rd if you're bottlenecking 2 cards already or don't add a 2nd card if you're bottlenecking one already because there won't be a performance gain.

http://www.anandtech.com/show/7189/choosing-a-gaming-cpu-september-2013/8

- AMD bottlenecks a single 7970 already since we notice a good 20-30% difference between the 4670k

- They added a 2nd AMD didnt get any performance gain and we see a 4670k with a single card outperforming a 8350 with two 7970's

At this step we're not sure if Intel did bottleneck it or not

- They've added a 3rd card and Intel didnt get any performance gain meaning it bottlenecked a 2nd card.

The lanes x4 at 3.0 shouldn't be a bottleneck, even 2.0@ x4 is enough.

[Javed shamim]

So you are unhappy with the performance of 2 cards?

 

If you have PCIE 3.0 enabled then those 4x slots are equivalent to 2.0 8x slots and I remember 2 way GPU in 8x8 on 2.0 being reported not to make a difference when the GTX 780 came out.

 

But 3 way + was reported to have issues, also your cards do communicate with each other more than previous generations through the PCIE bus now (connectorless Xfire).

 

I wouldn't do it personally, but someone might be able to give better advice.

Not unhappy just expected better performance for crossfired 290's.

BF4 5760x1080p o. Ultra (AA off) I get 50-80 fps depending on the map

And all that. I expected better so I thought adding one more 290 would keep it from

Dropping under 60fps.

[Javed shamim]

Don't add a 3rd if you're bottlenecking 2 cards already or don't add a 2nd card if you're bottlenecking one already because there won't be a performance gain.http://www.anandtech.com/show/7189/choosing-a-gaming-cpu-september-2013/8

- AMD bottlenecks a single 7970 already since we notice a good 20-30% difference between the 4670k

- They added a 2nd AMD didnt get any performance gain and we see a 4670k with a single card outperforming a 8350 with two 7970's

At this step we're not sure if Intel did bottleneck it or not

- They've added a 3rd card and Intel didnt get any performance gain meaning it bottlenecked a 2nd card.

The lanes x4 at 3.0 shouldn't be a bottleneck, even 2.0@ x4 is enough.

Thanks for that mate.

I'm not bottlenecking as far as I can tell

At the moment in crossfire 290's

The cpu usage hovers between 60-90% will gpu's

Are at 90-100%.

I've never had AMD cards before and I'm cautious before

Trying anything new lol

[Faa]

Thanks for that mate.

I'm not bottlenecking as far as I can tell

At the moment in crossfire 290's

The cpu usage hovers between 60-90% will gpu's

Are at 90-100%.

I've never had AMD cards before and I'm cautious before

Trying anything new lol

If the gpu is at 90-100% it's okay to get a 3rd one, I wouldn't do it if you couldn't even make it to 50% on each gpu what you get then is just 33% for each gpu and the same frames