To be fair to them, I guess I should've noted the complete context of what they said regarding that guideline: "After the CPU is decided on, RAM becomes the next most important component. In short, the more data you have running on your trading PC in the form of charts you’re watching, indicators, shorter refresh timeframes (down to a tick by tick update), browser windows open, etc., the greater your RAM/Memory requirements are. From our in-house testing with most platforms, you want to spec out roughly 4-6 GB RAM per 24-27” monitor being actively used for trading. That means for an active day trader with a 4x 24” monitor setup, you’ll want to run about 16-24GB of RAM for optimal performance. The important consideration for RAM is that you only need ‘enough’ RAM and having excessive amount of RAM won’t improve performance (it won’t hurt it either, it’s just a waste of your money). You only need to have enough RAM such that your programs and Operating System never exceed the amount currently installed – as long as that’s taken care of, your memory system will run well. If you run out of RAM, the data will spill over onto the storage device (SSD/HDD) and that process will be roughly 1/10th to 1/20th the speed of using system RAM – something you definitely want to avoid!" But appreciate your opinion. I don't know enough about this stuff to question anyone else's expertise.
HOGWASH! I posted earlier that my 4x, UHD monitor rig is running 1.6GB of RAM. Why would I need 16-24GB? In your own rig, you can run SIV (System Information Viewer)... available free.. and your Windows Task Manager to see how much VRAM and system RAM you're actually using. You won't benefit by having "gobs more of it"... you'll just spend money on extra capacity that you won't use. I suppose they could choose the parameters that would support their argument of needing "4-6GB/monitor". That is, choose the most "featured, complicated, intensive software displaying and archiving tic charts"... perhaps that would justify their "RAM needs" claim. I know for fact that running tic charts that are archived locally (likely on your storage drive... that means every tic is displayed on your monitor and is also written and saved on your drive) puts heavy/maximum pressure... likely meaning running your CPU at 100% all the time and your drive is writing several/many times every second... on your system's ability to cope with it all. But almost nobody does that... specifically because it stresses your hardware so much and will cause "update delays" as your computer tries to catch up with the data when markets are fast. Nothing good about that.
Perhaps you should question the opinion of someone who's trying sell you! However if you're doubful... you can buy a machine with 8 or 16GB of RAM and try it out. If the RAM is overtaxed, add more... easy peasy.
I was just using them as one of a number of sources -- including various posts from these forums -- to refer to re: specs/ideas for building my own computer, and have no plans to purchase a pre-built trading computer.
If you want my recommendation.... I would say that you SHOULD buy a pre-built trading computer.... a workstation from Dell, HP, or Lenovo. (I've had many computers over the years. One BIY job was enough for me. It was sort of fun but not worth the hassle.)