Hey everyone,

I had been simming in MSFS on an old i5 4690k and a GTX 1070, locked at 30fps with a 1080p screen. My settings were mostly medium to high.

I purchased a pre-built 3XS system from Scan which has these specs:

i9 14900KF

MSI slim RTX 4080 Super

64Gb of RAM

ASUS Prime Z970-A motherboard

Corsair RM1000X power supply

2TB M.2 SSD

Liquid cooling with 6x Noctua fans

Alienware AW3423DFW monitor

I installed MSFS and when I first ran it, all the setting were already set at ultra and the framerates in the A2A Comanche at my test airfield, Launceston, were between 82-84fps. I ran the sim with FG on. There frames were the same at Auckland, give or take a few FPS.

After about 10 days the frames suddenly fell to around 64 fps, all the time. I ran Memtest and the RAM failed with 233 errors. The system was sent back to Scan and new RAM installed. I reinstalled MSFS and was back at 80fps, but after four days, the frames fell to around 64fps again.

I also had an issue where the FPS was oscillating between 56-64fps every 2 seconds or so, but solved that by uninstalling FSUIPC.

After SU15, the frames have steadily decreased until now I get around 50fps on the ground at Launceston and about 46fps around New York with the same settings. I can't for the life of me work out what is going on.

The FPS display says I am main thread limited my CPU usage sometimes shows only 1 or 2% in CPU-Z. My temps are low throughout.

I can accept if these are acceptable framerates for my system, but I have seen people run 4K monitors with better frames than this, plus, I had over 80FPS consistently for 10 days when I first received the PC.. I have asked on the MSFS forums, but no joy there.

I would appreciate anybody's help with this.

If anybody needs anymore information on my setup to help diagnose the problem, please let me know!

 

Thanks,

 

Mat

Is your PC performing well in other situations? Do you have any games? You could run a UserBenchmark test and compare with similar systems.

My PC achieved a good score in TimeSpy and Scan remotely stressed the CPU and they were happy with the results. I guess I just can’t figure out where almost half the frames have gone. I wondered if some setting in my monitor was the culprit, but it is set at 165mhz, so I don’t think that’s the issue. I do have a month free on Game Pass so maybe I should download another game and try that. Thanks for the idea. 🙂

Is it possible you are affected by the 14900 intel issues? Are you still in the return window?

I have only watched a couple of YouTube videos about the instability issues, but thought that it didn't affect me as Scan said that they has tested the CPU and it was fine. I am out of the returns window, I believe. To be fair to Scan, they have tried to diagnose the issue, but as far as they are concerned, the system is running well. Thank you for your suggestion, though.

First, the CPU utilization reported by CPU-Z is the average across all the cores--in the case of a 14900K, all 24 of them.  So you could have a few cores maxxed out (hence the main thread limit) and still have a very low average utilization.

How are you measuring your frame rate?  The FPS display in the sim reports the rate that frames are being produced by the sim--with FG on, the actual frame rate to the display is higher than the FPS counter reports, as the GPU is generating additional interpolated frames interleaved between the sim-generated ones.  The Alienware monitors have an on-screen display you can turn on with the monitor's controls that will show you the rate frames are being sent by the GPU to the monitor.  So if you're seeing 50 fps in the sim's FPS display, you should be seeing a much higher rate at the monitor with FG on, but again, the sim's FPS display won't report that. 

Most of my cores are at zero and at one point, there were no cores above 5% and that was just one of them, a couple were at 1-2%. No cores are ever anywhere near even 50% usage. This was checked in CPU-Z and the task manager (I think). A separate FPS counter does indeed report roughly twice the in-game FPS with FG on, I know that I am lucky to finally be able to afford a nice system after a decade of my old 4690k and don’t want to seem ungrateful, but it’s just so frustrating that on the ground at Launceston I am 40fps down on what are essentially the same settings. The only thing that has changed is a sim update (SU15). I feel like I am obsessing over this, but I guess I just need to know my CPU isn’t on the fritz. I do appreciate your taking the time to reply to this, though. 🙂