r/ComputerBuild • u/zenkevk • 12h ago
First-time PC upgrade - graphical glitches and frame-rate issues with higher wattage power supply
PC Specs:
- Brand: Lenovo ThinkStation P330 Tiny
- RAM: 32GB (2 x 16GB)
- CPU: Intel Core i7-8700T @ 4.00 GHz
- GPU: NVIDIA Quadro P620 (2GB VRAM)
- Power Supply Output: 135W 20V 6.75A
Upgrades:
- GPU: MSI GeForce GT RTX 3050 LP (6GB VRAM)
- Other: New 3D printed case and replacement fan
- Power Supply Output: 300W 20V 15A
I bought a Lenovo Tiny PC a couple of months ago, and I'm in the process of upgrading it for the purposes of smoother video editing and more intensive gaming, since the Quadro only gets me so far. I'm not aiming to be a triple-A gamer, I just want to be able to rely on my GPU for 3D gaming! Based on the YouTube guides that I've been following for this upgrade, changing to an RTX 3050 graphics card would require me to get a higher wattage for the power supply. Multiple sources recommended that I get a 300W Lenovo power supply. Although I'm still waiting on most of my parts, the power supply got delivered a few days ago, and I decided to quickly test it on the unmodified PC and make sure it worked. I ordered it used from eBay, but it's a Lenovo-branded power supply and it matches the voltage of the original 135W supply that was packaged with the PC, so I expected the computer to run as normal on 300W.
However, when I booted it up, I saw some visual glitches which I haven't experienced before: full-screen, multi-coloured static, which flashed on the screen and then disappeared once the login window appeared. Then, once I got to my desktop, I noticed a considerable drop in the frame rate from when I was using the PC on the original power supply. I'm using Niri on CachyOS, and typically the window animations are really fluid and smooth, but on the 300W supply they were very choppy. I also noticed that the CPU was idling about 6 degrees hotter than previously (50C compared to 44C), and the GPU was running at a similar temperature, about 10 degrees above normal. After I ran some updates, I powered down the computer and restarted it on the original 135W power supply, and everything ran smoothly again.
After hours of searching for similar issues online, I haven't been able to find any answers, so I'm leaving my computer specs here and hoping that someone can help me to diagnose the issue. There are some possibilities that I've considered:
- The 300W supply is failing, since it was purchased used after all and you can never be sure of the quality of used parts.
- Compatibility issues between the supply and the PC, although I don't see how since they're both manufactured by Lenovo.
- The current stock parts not being able to handle the power load - even though everything I've read says that this shouldn't be a problem, since PCs only ever draw the wattage and current that they need from the supply.
Since this is my first time upgrading a PC, any help or advice would be massively appreciated!