Is it's very dated hardware and any change to drivers or configuration and blammo, it tanks. You could spend a lot of time finding Elmo (the cause) or toss a GPU in there to make it fly.
In short, reinstall the OS to the state where ti worked and NEVER EVER allow driver updates.
That machine's time has passed and can really upset those that want to spend their time on this (or get others into the tar pit.) What would I build?
Something from https://www.reddit.com/r/PCMasterRace/wiki/builds
So I've been having this extremely frustrating problem for like 5 years now, I've been on countless forums and no one seems to know a thing. Long story short, I built my first gaming pc in 2012 and it worked great for a year, no lag, everything was silky smooth, then it started lagging out of nowhere. By lag I don't mean random lag spikes, every single game just ran at a lower fps than before (around 10-15 lower) constantly. After a windows reinstall and multiple hardware replacements, I just decided to buy a new pc. I know how unlikely this sounds but it had the exact same problem, so I returned it and got another one. Same issue again. After returning it I got a PS4, because that made sense to me for some reason. You can probably tell where this is going. I know that consoles are locked at 30 fps but mine was running at freaking 20. Oh, I forgot to mention that the pc's I returned were more than decent and I was only trying to run games from 2010 or 2011.
Right now I'm using my 2012 computer, here are the specs:
-AMD Athlon II X3 450 3.2 ghz
- Seasonic S12II-520
-Gigabyte GA-MA78LMT-S2
-Onboard graphics
-A 500 gb WD
-6 gb of kingston ram
So naturally I started looking into the things that came in contact with all these 4 systems, the ethernet cable and the power cable respectively. I think it's safe to rule out the ethernet cable so we're left with the power cord or better said the electrical current. Now, the apartment building I live in is really old and so is the wiring. A few weeks ago I ran prime95 and some other cpu stress tester and had HWmonitor and cpu-z opened to look at the cpu voltages. They were fluctuating like crazy, between 1.125 v and 1.475 in full load and so was the core speed, between 800 mhz and 3.2 ghz. It's doing the same thing during browsing but less frequently. I don't know that much about hardware besides the common sense stuff but that can't be normal right? I've never overlocked anything or even messed with the bios settings by the way. Another thing I should mention is that back in 2012, 7 months or so after the lag started manifesting, the onboard audio and lan got fried (or at least that's what I think). I had a quality PSU that I had just bought, so that couldn't have been the cause. Also, the temps are fine.
The reason I'm making this post after all this time is because I'm in the middle of building another pc and it would be great if I somehow managed to solve this issue before finishing it.
Thanks in advance.

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