4gb is at best borderline for the current Windows OS and it means you've got a little futureproofing for the next few years.
@Pezza24
I have an ACER laptop with 6GB RAM its getting on a bit but still performs well for what i use it for which is basically forum and internet use it plays HD video with no problem but if i was buying a replacement today i would go with 8GB if i could afford it, you can never have too much RAM.
My last laptop had 4GB RAM and as you can see below 4GB will do the job (depending on 32-bit or 64-bit) but when i bought my current Laptop i did notice the difference so for me its a no brainer go with 8GB if you can afford it.
4GB RAM
If you're running a 32-bit operating system then with 4GB of RAM installed you'll only be able to access around 3.2GB (this is because of memory addressing limitations). However, with a 64-bit operating system, you'll have full access to the whole 4GB.
The difference in performance between a system with 2GB of RAM and one with 4GB is like night and day. Even on a 32-bit system that limits the RAM to a little over 3GB, the performance boost is well worth the cost. Not only do applications run faster, but you can also run more applications simultaneously, which comes in handy if you run suites like Microsoft Office or Adobe Creative Cloud (say you want to run Microsoft Word and Excel, or Adobe Photoshop and Lightroom).
If you have a 64-bit operating system, then bumping the RAM up to 4GB is a no-brainer.
All but the cheapest and most basic of Windows 10 systems will come with 4GB of RAM.
8GB RAM
Now we're into performance territory. If you're serious about your PC, then I consider this to be the new default. If you're buying or building a machine dedicated to photo or HD video editing and rendering, or just want a fast system, then 8GB of RAM is the minimum you should consider to avoid frustration.
This is the amount of RAM recommended by Adobe for users running Creative Cloud applications.
8GB of RAM is not expensive. Sure, get the OEM to fit it into a new system and you're likely paying a premium (especially if that OEM is Apple), but from an aftermarket supplier, this can be had for under $40.
8GB is the minimum amount of RAM new Macs ship with.
https://www.zdnet.com/article/how-much-ram-does-your-windows-10-pc-need-2019-edition/