Question Diagnosing sudden performance decrease

[dalerhendricks]

Hi all,
I have what was until recently a pretty capable desktop, capable of playing games like Baldur's Gate 3 or Metro Exodus smoothly at medium+ settings, and it just recently started struggling with even very graphically simple games. File Explorer and other basic software is also quite lethargic, so I assume it's not just a graphics issue.
I haven't been able to pinpoint an exact time it happened or link it to a specific update or event, and have been trying to work through the standard troubleshooting steps without any luck so far.

What I've tried:

• I have restarted the computer fully.
• Windows is up to date, as are my graphics drivers.
• Defender hasn't caught any viruses or malware.
• I was running with pretty full drives but I cleared them out and it didn't help.
• I took the side off and cleaned the dust out, there wasn't a ton in there.
• I ran Windows Memory Diagnostic and it found no issues.
• I reinstalled Windows from within Settings, not from install media (couldn't find my flash drive to make the media today)
  • This seemed to help a bit with general responsiveness, but framerate still absolutely tanks in games

It is a Dell XPS prebuilt, I've had it since I believe Spring 2022.
My specs are:
Motherboard - Dell 0R6PCT A01
Processor - 12th Gen Intel(R) Core(TM) i7-12700 2.10 GHz
RAM - 2 x 16GB DDR5 4800 (part number is HMCG78MEBUA084N)
GPU - AMD Radeon RX 6700 XT
Hard Discs - 512 GB SSD (OS plus a few things), 1TB HDD
on Windows 11

I did a little snooping with MSI Afterburner last night but am not 100% sure what to look for. I ran Starcraft 2 for a bit and the ingame monitor had me at about 1-3fps, Afterburner reported no temps above 45C, was sitting at ~15GB ram in use (45% said task manager), and the GPU had a couple spikes of usage (up to 60% or so, then right back down) but was mainly sitting at hardly used.

What should my next steps be? Any insights on things to try, or useful benchmarks to take to narrow things down?

 

[Ralston18]

PSU: make, model, wattage, age, condition (original to build, new, used, refurbished)?

Disk drive(s): make, model, capacity, how full?

You mentioned Task Manager.

You can also use Resource Monitor, Performance Monitor, and Process Explorer to observe what the system is doing or trying to when performance decreases.

Use all three tools but only one tool at a time. Leave the tool window open and observable while you work and game. What for what changes when performance decreases.

Process Explorer (Microsoft, free):

https://learn.microsoft.com/en-us/sysinternals/downloads/process-explorer

Look in Reliability History/Monitor and Event Viewer. Either one or both tools may be capturing some error code, warning, or informational event at the times performance decreases.

Take your time, be methodical, watch carefully, do not jump to any conclusions.

 

[dalerhendricks]

PSU: Dell L750EPS-00, 750W, the date code is R2146, I haven't managed to decode that yet but wanted to get a reply out quickly, the PC was new in 2022.
SSD: NVMe PM9A1 Samsung 512GB, currently at 298/456GB free
HDD: Western Digital WD10EZEX-75WN4A1, currently at 512/931GB free

I'll work my way through those tools you mentioned this evening and see if I can catch anything, thank you!

 

[geofelt]

What might have changed since all was well?

What is your cpu cooler? Possibly it has come loose.

 

[dalerhendricks]

@geofelt I'm really drawing a blank as to what might have changed. I can't think of anything unusual that might have happened during the last couple weeks to cause it. I did have it opened up to clean and check for dust and nothing seemed to be loose. One of the case fans was never plugged in in the first place (thanks Dell, very cool) but that's fixed now.

I have a reproducible severe lag in a game that should be well within my specs, and has run totally fine in the past (Timberborn). I brought up afterburner and got this image (I added the red lines to help line up where the lag happens). If I cause that lag in game, but the cpu and gpu usage both drop because of that, what is the limiting factor?
Trying to find other correlations using the tools Ralston18 mentioned now

 

[JohnBonhamsGhost]

PSU: Dell L750EPS-00

i would do some research into the actual quality of this unit's build.
with Dell/Alienware OEM units there can be a large difference from cheap outsourced junk to higher quality in-house generics.

though the option to switch to a trusted high quality unit may not even be an option with the OEM motherboard still in use.

I reinstalled Windows from within Settings, not from install media

i would much rather have a fresh MS Windows installation rather than the included Dell OEM Windows versions.

 

[CountMike]

Run program OCCT
https://www.ocbase.com/download
Stability and benchmark while monitoring core frequencies, temperature, voltage and power,that should tel you about HW state without involving Windows.