Choosing right RAM stick for my laptop

You should buy exactly same speed, same timings and if possible same brand.
Download, extract and run HWiNFO
It's a portable, don't need to be installed.
Under the memory tab you will find all the current memory specs

OK, got two 4GB modules today. Thought I'd run the old Windows Experience Index test prior to swapping them. I notice the memory rating isn't the bottleneck on that - the base index comes from the graphics, since I've only got integrated graphics maybe. Anyway, hopefully the 8GB on two channels will speed certain things up over 2GB on one. Problem is the WEI got the the CPU test and it did a hard shutdown, presumably overheating the CPU. Not sure whether to try again after a restart (I had a bunch of other things open and I think Kaspersky might even have been scanning) - don't want to keep overheating the chip now I've spent a fortune on memory! (joke - £12, and £2.90 for the bus ride). Wonder if PassMark might be kinder or harsher on the CPU. I'm actually using a slightly over-rated voltage power supply after the old one died - seems to work fine, but perhaps can't cope with the current demand (says he like he knows anything). Anyway, I did a WEI test in 2017 with much the same gear, giving this rating...:



Incidentally, I was still tempted to go for the very cheap option of another 2GB, but the only ones they had in stock were 1600MHz, and the guy said that although it would still be faster than before, it would be throttled down to the 1333MHz of the original one, and I decided to get two that match (although they are different makes). Actually glad to get second-hand now for the environment, assuming they work and I don't have to return them!

You should have a hardware monitor.
Download, extract to a folder and run Open Hardware Monitor
Under options you have start with windows.
You can configure what to show on the tray and on the gadget.

For someone that suspects that it had a over temperature shutdown, a monitor is very useful. And it takes less than 7M of memory

Megahertz07 said:

You should have a hardware monitor.
Download, extract to a folder and run Open Hardware Monitor
Under options you have start with windows.
You can configure what to show on the tray and on the gadget.

Thanks for that, it's proving quite useful.
This is weird. I wasn't aware of any overheating issue, decided to upgrade my RAM for very little reason (too lazy to organise bookmarks in browser and close a bunch of tabs, that is), thought I'd test the speed before changing over to the 8GB, and the high stress test of the Windows Experience Index caused it to shut down - fan going like mad. Then I installed Open Hardware Monitor - not the other one - and while I was getting to grips with that Kaspersky did its routine scan and I watched the temperature hovering around 60C., edging up towards 70. Fine. Then fairly suddenly it shot up again at one point and shut off before I could do anything. So yeah, it seems I've got an overheating problem. It's possible it's done that once or twice when I've left the machine running, come back and it's powered down when it would normally just go into sleep mode. I'm not sure whether I should start a new thread. Yes, probably will - then finish the upgrade. I'll call this issue of the memory modules solved unless something untoward happens (when I find the button - that's disappeared now!). Cheers. You guys've been great.

OK, I've posted about the overheating problem (I thought Performance and Maintenance was a better place). Overheating: Power Options, supply voltage, powercfg -energy errors?