Elden Ring performance on PC is not ideal especially if you play on older hardware but there are a couple of steps you can do in ordered to improve the FPS and fix stuttering.
Elden Ring PC port is a mess and the review bombing on Steam is already in full swing. Regardless of the hardware, it seems that the game is constantly stuttering and has some serious frame rate drops to the point where it becomes unplayable.
From Software acknowledged the performance issues and will be working on patches to improve the frame rate but until then, players are on their own to come up with a solution.
Luckily, some tweaks can boost your FPS in Elden Ring. Here are some of them but please keep in mind that these are not guaranteed to work on every PC.
Change Power Plan to "High Performance"
Search for "Power Plan" in the Windows Search bar. Click on Choose Power Plan and select "High Performance" or a different high-performance mode your PC is offering.
Set "Shader Cache Size" to "Unlimited" in Nvidia Control Panel
Go to Nvidia Control Panel then Manage 3D Settings. Scroll down until you find Shader Cache Size and set it to "Unlimited".
Disable Steam overlay
Find Elden Ring in your Steam games library, click on Manage (gear cog icon on the right side of the screen) then Properties. Uncheck the "Enable the Steam overlay while in-game" option.
Download and install the latest graphics drivers
Launching Elden Ring without previously downloading the latest drivers will result in terrible performance across various graphics cards.
Before you start playing, make sure you have the latest version of drivers installed. Below you'll find links for driver download from both Nvidia and AMD website.
If you play Elden Ring on PC, sadly, there isn't much you can do right now to improve the performance of the game if these fixes don't work. Your best option is to simply wait for more patches that will hopefully bring additional optimisation and fixes.