A swap larger than the RAM is only required if you want to use hibernation.

regarding whether i can use my ssd as a buffer memory, i will need some more info on how to investigate and implementation

Forget about this idea. This was promoted for a while by Intel, they also had a product for that, and Seagate also had some hard disks with SSD cache on board in the portfolio, but never was really adopted in a bigger scale. This is sort of dead by now.

Check the manual, specifically pages 13 and 82.

Edit:
You may also want to read this post at one of the better known thinkpad forums.

Best,

A.

it seems to me that the suggestion is to buy 2 x 4 GB of ram as an update and save a little on the purchase.

regarding whether i can use my ssd as a buffer memory, i will need some more info on how to investigate and implementation

is OP having a specific issue or just desire to update/upgrade machine?

what about watching for a newer/better used machine to become available at the right price?

i have an ssd 128 gb that can be inserted instead of dwd
but is there a method to configure it as a buffer
and is it possible and useful

Depends on how it is setup by the replacement device used. If it is a direct connection to the internal Hard Drive controller allowing it to boot the machine then it can be damn useful. That type of arrangement can be the same as replacing the internal hard drive. You need to determine the way it connects to the machine, the speed of the connection it gets when in it. But generally it is good to try and use it as your install to boot from to see if it will speed up your machine. If Camtaf is correct with the specifications he posts for your machine and it has four slots with maximum capacity of 16GB for the machine then the ram you show is incorrect for your machine as the most it will take are 4GB higher speed modules and you link to are 8GB. Before buying anything make certain of the return policies in the event what you get does not work with your machine.

Now I have looked for them this place suggests 32GB or 4 X 8GB modules are supported.

https://memory.net/product-category/len … 30-series/

As does the Kingston web site.

https://www.kingston.com/en/memory/sear … 530-series

And this German site says the same thing as well.

https://www.compuram.biz/memory/lenovo/ … quad-core/

The one thing they all have in common is the 1600mhz for the ram speed, if replacing your ram in the end then this is the speed you need to get to run it at its full potential. And as I have already said make certain any place you buy from has no questions asked no hassle returns policy. There  is no sense wasting your money if you find what you have bought does not work properly and they will not let you return it.

However, having said that the speed between 4GB & 8GB of ram won't be that great, (I use 2, 4, & 8GB machines) - I think a better upgrade would be changing to an SSD disk from that old spinner...

no 'V - not buffer - not ECC',

No clue on the V - not buffer, there is buffered and unbuffered memory, but the not ECC is what you want for it. The error correcting (ECC) memory is used for servers not consumer machines like a laptop. Perhaps you could post link to the memory so people can see the exact model you are thinking of buying.