SSD

[NITHIN7]

My system is very slow with 4GB RAM & 1TB HDD. In order to have better performance, which SSD type should I use which my PC supports and which is the best manufacturer for my 15s-gy0001au HP system?

[Huffer]

Here is the Service Manual:

Manual 

In general, this model series has an M.2 slot that will accept a 2280 form factor NVME SSD. I would advise you to install one of those, but your specific model has the lowest processor, Athlon Silver. Although the Manual does not say so, frequently models with the lower end budget processor do not actually have support for an M.2 SSD. So I suggest you look at replacing the very slow 5400 rpm spinning mechanical hard drive with a 2.5 inch SATA SSD. It will be a huge performance upgrade. I would also recommend you increase the memory to 8 gb. However, its also often true that the lower end systems have only one memory slot. If you brought it to me to upgrade I would first open it and check to see if a second memory slot and/or M.2 slot is actually present. The Manual suggest they are, but as I said I have doubts. 

Post back with any more questions, please.