Radeon RX 480 crossfire performance problem

Pawemol12

Honorable
Sep 20, 2015
19
0
10,510
Hi all,

I have problem with the performance of these card. With single card enable I achieve a good amount of fps in games but with cf enable I get lower fps than a single(in most cases) + freezes. I have latest amd driver's (Crimson 16.12.1) and updated windows, latest motherboard bios version so I don't rly know where the problem is ;/


I suspect it's a problem with power draw when im running it in crossfire but I have got 1350w platinum psu so it shouldn't be the problem. Here are screen of gpu power draw diagram when only single card is enable:

http://screenshot.sh/n7gAAFyBEx0fb

Diagram when cf is enabled:
http://screenshot.sh/oemfX8WKM9OJ9

Here are my specs:

MotherBoard: ASUS M5A99FX PRO R2.0
CPU: AMD FX-9590 4.70GHz
PSU: Enermax 1350W Platimax
HDD: Plextor 128GB 2,5" SATA SSD M6S Series
SEGATE st4000dx001-1ce168 4 TB
GPU: 2x ASUS Radeon RX 480 8GB STRIX OC
RAM: 4x DDR3 GOOD RAM 8GB 1600MHz Play CL 10

Rly I don't know where the problem lies ;/ I have searching for solution like 3 days but none of them works.


 
CF and SLI performance is rather dismal ... while SLI scaling was great w/ the 9xx series (scaling @ 70% average, 96+% in demanding games) , making the twin 970 option a virtual no brainer with 40% more performance than the same price single 980. I can't justify it at this point with the 10xx / 4xx series

Only 39% at 1080p

perfrel_1920_1080.png


 

lakimens

Honorable
Well, that CPU is just bad and probably not overclockable, since it is an overclocked FX-8350.
You can try to overclock it with AMD Overdrive to get better performance, but chances are slim.
Best wait for Ryzen and then decide whether you go AMD or Intel and get a CPU.
 

Pawemol12

Honorable
Sep 20, 2015
19
0
10,510


Many games depend primarily on a single fast master thread for performance.
Windows will spread such activity around among all the available threads.
A single task that needs 100% of a single thread will show as an average of 13% busy on an 8 core cpu.

To test this assertion, do an experiment with YOUR games.

Try removing one core. You can do this in the windows msconfig boot advanced options option.
You will need to reboot for the change to take effect. Set the number of processors to less than you have.
This will tell you how sensitive your games are to the benefits of many threads.
I am guessing that if you operate on 7 threads you will see no difference in performance.
You probably will do about as well with 4 threads before you lose significant performance.
 

This is how long it takes CPU's to create the fps per frame in crossfire. As you can see it takes the AMD way longer then even the old 3770k. This is due to fact each core is slower on the AMD.
SkyrimUltra1920CPUBottleneck2013.png

SkyrimUltra5760CPUBottleneck2013.png
 

Pawemol12

Honorable
Sep 20, 2015
19
0
10,510
I have installed msi afterburner to monitor my gpu usage, cpu usage in game. I have noticed that when only 1 gpu is running I have nearly always 100% gpu use but when cf is enable then it is on 20% or even lower (on both gpus) ;/ Cpu clocks on all cores are 60 - 80% so I think I will not have to replace my cpu becouse im not able right now.

I will post YT videos later to show you the comparasion of using only one gpu and using both in cf.

Edit:

In heaven benchmark on max settings both cards work on 100%. Idk why in game they won't :/
 


1. I would avoid youtube reviews / compares. Anybody w/ a web cam can post a video, that doesnt men they have the knowledge and experience to conduct a reproducible test result. Unless associated w/a well respected site, I'd just ignore them.

Search youtube for "970 3.5 GB problem" and you will see dozens of yahoos demonstrating the problem ...a problem which a dozen reputable web sites tried to reproduce but were unable to do so under normal usage without doing really really strange things.

2. Assasins Creed is a freak ... AC:Unity was an extremely poor console port sucked RAM like crazy. As for AC:Syndicate, you should expect a 82% boost in fps.

acsyndicate_1920_1080.png


3. Is your card throttling ? Dunno what case you have or number / specs of fans but the 480 runs very hot... the intake cooling air for the top card is essentially the hot exhaust from the bottom card. In CF, the system will regulate the speed of both cards to the lower of the 2 cards. So if the top card throttles, the bottom card will downclock match it.

4. Cores rarely provide any significant impact to gaming. Windows will not automatically spread this out to use all cores. You can look at affinity setting in Task Manager and most games will default to a single core and it will stay like that unless you change it. In my experience, setting it from 1 -2 has a noticeable impact, going from 2 to 3 not so much but the number changes minutely, going from 4, to 5, 6, 7, 8 has never changed anything in my experience.
 

Pawemol12

Honorable
Sep 20, 2015
19
0
10,510
2. I have maybe 10% boost in fps example. Normal I have on average 75 fps in one scene and when I repeat it in crossfire I get 85 fps lol.
3. I have very good cooling, clocks are always on max (1310 MHZ). I have run 20 min max settings heaven benchmark and always 100% gpu useage on both gpus.
4. I have noticed cores 1 - 6 in AC Syndicate are most used but with cf enabled (60% - 70%) average use on one core.

I think my problem is software related as in heaven benchmarks gpu usage stay the same (both 100%) but in game they are jumping like one is 100% and another is 0%. Or one is 99% and other is 10% etc.

So from crossfire in games I get no benefits, in some cases lags and worse performance than single gpu.

Edit:
Well when heaven is performing these cards actually are making really loud noise but when gaming they are silent :/
 

Wakonyosai

Prominent
Mar 16, 2017
1
0
510


Did you try setting the profile for the game you want to play in the Crimson settings menu? I had similar issue with BF1untill I setup the profile.
 

Pawemol12

Honorable
Sep 20, 2015
19
0
10,510

MaDDD

Reputable
Jan 13, 2016
268
0
4,860
My guess it that since your CPU would already bottlenecking the performance of a single 480 in quite a lot of things, adding a further one is making the CPU struggle more and therefore performs worse. I may be wrong but it makes some slight sense to me.
 

MaDDD

Reputable
Jan 13, 2016
268
0
4,860
CPU usage means nothing if the things you are using only utilize 1/2/4 cores, as most games do. Other things come into consideration such how much memory the CPU can handle and send to the GPU and such. There is a bottleneck, there was one when comparing my OC'd fx 8350 @ 4.8 GHz and a single GTX 970, compared to my Ryzen 1700x and the same GTX 970.
 

Pawemol12

Honorable
Sep 20, 2015
19
0
10,510
But when I run for example. AC Syndicate on max possible settings I get no stuterring and better fps than on medium or low settings ;/ That is the problem here not cpu ;/
 

Boozer Tech

Prominent
Apr 17, 2017
1
0
510


I have to say this is pretty rude and where is your proof or knowledge that it is a cpu bottleneck I run cfx 480s with a fx 8370 and have no issues with cpu bottlenecking.