i7 4790K possible bottleneck of RTX 2080?

[filip.kotlik]

Hi,

so the best will probably be list my specs first:

CPU: i7 4790k 4.4 ghz
MB: asus z97-ar
Ram: kingston 16 gb ddr3, 1866mhz
Gpu: rtx 2080 msi gaming x trio
Psu: fractal design 750W 80 gold
Windows 7
Monitor: LG 2560x1080, 75hz
Cpu cooler: noctua... (its massive)

The problem:
Recently i purchased the new rtx 2080 MSI gaming x trio. Upgrading from 980 ti, i thought my fps will fly trough the rooftop. Well that didnt happen. Actually i see only slight performance boost in games. I try to figure out where is the problem using msi afterburner and other build in benchmarks in games. The most problematic is the assassins creed odyssey and origins, where my fps drops under 30 fps, the avererage is 50. Msi afterburner shows that my cpu has 99% usage, and gpu only 60%. I tried to set Resolution modifier to 160% but fps stsyed the same, only gpu and cpu now both on 99%.

Another problematic game is for honor, where my fps is over 120 fps without supersampeling enabled, with it enabled it goes down to 50 fps, but i hsve to have it enabled and set the resolution modifier to 75% because when on the 120 fps, i am experiencing massive fps drops(especially when it rains ingame) from 120 to 30fps, sometimes it locks fps to 30 or 60 all by it self and its super game breaking when tryi g to be competitive, this is weird because vsync is disabled.

Another problematic game is kingdome come deliverence, where i noticed the slightest fps boost, game plays same as with 980 ti, 10 fps more max, textures load still incredibly slow like before, i thought that with more gpu performance this would be eliminated.

Anyway so far i tried: reinstall gpu drivers like 3 times, roll back to the older ones, bios update, nothing helps. I am suspecting is probably the cpu bottleneck but i saw many videos where people have better performance with those games. Also cpu usage hits 99% only in AC games, in for honor and KCD only around 70% So my question is: whst else may be the cause of this trouble? I heard that it may be the slow ddr3 ram, or even dx11 or windows7.

Sorry for long post, i tried to be as specific as i could

 

[Dragos Manea]

RAM can run in Single Channel, Dual Channel, Quad Channel (for HEDT chips), single channel is the most basic, dual channel means that it doubles the data transfer bandwidth to the cpu but it must be in certain slots and the sticks must be identical. Quad channel is where the banwidth is increased 4 times but only HEDT chips has this (X99, X299). Also in games is not much of a difference between dual and quad. On short you increased the data transfer to your cpu by 2 times by activating dual channel instead of single channel how it was working before.

 

[filip.kotlik]

RAM can run in Single Channel, Dual Channel, Quad Channel (for HEDT chips), single channel is the most basic, dual channel means that it doubles the data transfer bandwidth to the cpu but it must be in certain slots and the sticks must be identical. Quad channel is where the banwidth is increased 4 times but only HEDT chips has this (X99, X299). Also in games is not much of a difference between dual and quad. On short you increased the data transfer to your cpu by 2 times by activating dual channel instead of single channel how it was working before.

Nice, seems kinda weird that cpu is around 95% even before when the ram was not trasfering data fast enough and after fixing it the usage was still high but cpu was actually working with 2 times more data

 

[Karadjgne]

Eh. Ram in dual channel has double the bandwidth capacity of single channel. Capacity, not transfer speed. A 4Gb stick can hold @4Gb of data, the bandwidth is how much of that data can be shunted at any 1 time to the cpu, timings is how fast the data is made ready to be moved and speed is how fast the ram works with that data. Basically. So take 2x sticks in single channel, the cpu grabs data from one stick, then the other, as data is made available. In dual channel, all that data is pulled at the same time. You get about a 20% performance benefit from dual over single, but most times you'll not even see that unless the bandwidth is saturated. For most instances, single and dual channel are pretty much equivalent as there's simply way more available bandwidth than there is data to fill it up. Kinda like there's exactly no difference between pcie x8 and x16 since there isn't a gpu made that'll fill up pcie 3.0 x8 bandwidth, making sli a possibility with no loss of performance due to hardware.

Since an i7 is at 95% on 1080p, dual channel has made a visible difference, there's something else at work there that's saturating not only the rams bandwidth but also 95% of 8 threads. That's a huge amount of data being used, far more than is normal for any game. You'd expect that kind of usage under gaming and streaming simultaneously or malware or other such. The only time (other than stress tests) my i7-3770K has seen over 60% usage was due to a nvidia corruption of the prefont cache, where all the fonts in my pc were treated as separate files (its not uncommon an error with nvidia) which created huge amounts of cpu usage (25%-55%) at idle.

 

[filip.kotlik]

Tottaly not malware, i have antivirus takinng care of that pretty efficiently. I watched som benchbarks at youtube according single and dual channel difference and it matches the difference in my case. Anyways AC Odyssey and origins are really cpu heavy, bringing even 8700k above 80% usage so i am not suprised 4790k has hard time to keep up. I am just glad my gpu is finnally hitting above 90% usage

 

[jesselafantaisie]

Yes people really don't understand how important dual channel is so much false information based on 5-10 year old benchmark when RAM speed was a lot less DUAL Channel is a must for gaming now. Also games like Assassin's Creed take advantage of faster memory big time. Just look at this Assassin's Creed Origins benchmark (at bottom of post) it has me tempted to upgrade from 16gb DDR3 1886mhz to DDR3 2400mhz but prices are crazy 130$cad for 16gb ddr3 2400 ridiculous price for temp upgrade but I am running at high framerates like 1080p144hz/120hz for shooters like battlefield v and have a slight minor cpu bottleneck causing FPS to dip every now and then also with Assassin's Creed Origins i have bottleneck 1440p60hz while in Odessey I don't have bottleneck I cap FPS at 60 for these games and play them on my 4KTV as they will bottleneck pretty much any CPU if you uncap FPS I wonder how many with their 8 series and 9 series have slow DDR4 ram like 2400.

Obviously in my case going from 1886mhz to 4000mhz would make a huge difference and is where most of the performance boost will come from when upgrading my CPU. I have Gigabyte RTX 2080 Gaming OC, 16gb (4x4gb) Crucial Ballistix Tactical Tracer (B/O LED) 1886mhz, Intel i7 4790k @ 4.6ghz. Overclocking my ram to 2133mhz fixed my Origins bottleneck as well I still get really high CPU usage but my FPS isn't dropping every 30 secs in populated citys like it was before.. Keep mind the best course of action to prevent bottleneck while waiting for new CPU is to CAP FPS at your refresh rate so if your running at 75hz use msi afterburner/riva tuner to cap fps at 75. Also you want to use highest settings possible that give you full GPU load. Lower settings will put more strain on CPU thus potentially creating bigger bottleneck. Also don't upgrade to any i5 even 9600K as its not the worth the biggest boost in performance gaming wise will come from the faster ram. So buying mobo/cpu/ram for like 800$ would be a waste just to get performance boost from faster ram if your going to upgrade its best to go with i7 8700k on sale or i7 9700k/i9 9900k. But like someone posted earlier its most likely best to wait and see how new Ryzen CPUs perform and Intels next series. Since your not gaming at 144hz or 120hz trying to get 144fps/120fps your not really in need of major upgrade just cap fps at 75 and you'll be fine. Theres really no point and uncapping FPS beyond refresh rate unless you can keep consistent 150-200FPS with out major drops once you get into 200-300fps range fps drops begin to not matter as going from 300fps to 240fps is essentially same frametime difference as having 120fps and dropping to approx 110/100fps.
Frametime at 30fps=33.3ms 60fps= 16.6ms 75fps= 13.3 90fps 11.1ms 120fps= 8.3ms 240fps=4.2ms 300fps=3.3ms. So dropping from 75fps 65fps is going to feel much worse then dropping from 120-110fps and dropping from 300fps to 240fps you probably won't notice.

https://www.youtube.com/watch?v=_XwcnZzBQaQ