How to restore my laptop's performance to its original state

(2011 Dell XPS 15 L502X, Core i5-2410M, 4GB ram, 7200rpm HD, Nvidia GT525M 1GB, Win 7 64)

I have done a complete factory restore, but it is still slow when doing simple things like loading Word, or when I click on the home button it takes a second or two to load, and when I hover the mouse over the menus it takes a couple of seconds to react. The slowness it most evident when I, say, use Chrome for a while and then suddenly go on the start menu and open something else. But within Chrome, everything is responsive. Word and Excel etc all perform quite slowly for some reason. Overall, Its not how I remember it when it was new, despite having done a complete factory reset. Why is this? And how can I get the performance back?

I've downloaded a couple of monitoring programs (CPUID HW monitor, Real Temp) to see the temps of various components, and currently my CPU and HDD are sitting at 60 C (143 F) and 52 C (125 F) respectively whilst browsing Chrome with 7 or 8 tabs open. Task manager says my CPU usage is about 15% and RAM usage is 2.4GB. The fan is on constantly but at a low, occasionally rising up to medium speed periodically. I have a feeling that it may a rebuild and removal of dust or perhaps a new HDD.

I've read a lot of stuff online and they all seem to be different, a lot telling me to defrag my disk, and delete all temporary files, recycling bin etc. I've tried this and it's not helped much. As you can probably tell, I'm not very knowledgeable with computers... hopefully you can all enlighten me here.

It's never going to be unfortunately.
Your perception of 'fast' has been set by your current machine and when you first got it it was a step up from what you had before. As you haven't had this update it will never feel as fast now.

Also, there is a pure psychological mind trick of associating spending money on something and thinking "it must be faster" I don't suppose you kept any benchmarks you did of the machine when you got it first time round to compare to now? That would be good evidence of the perceived loss in performance.

Given you have a mechanical hard disk the best way to get your machine feeling snappy and fast again would be to get an SSD and clone your disk (or better still do a fresh install or get a friend to assist)
There is no better or more cost effective upgrade than an SSD to give improved system response.

I haven't got any benchmarks from when I originally got the machine. I can understand that a lot to do with this is perception, but I think that there's something additionally at play here.

I've made a bit of progress with a few things. Firstly I've found out that my CPU is performing well, if a little hot. Under a stress test, it was maintaining a clock of 2.7GHz at about 92 C (198 F). Its a 2.3GHz CPU with 2.9GHz boost, so I'm wondering why it didn't boost all the way. There was no thermal throttling, but the temp seems a bit high (?) so I'll take it apart and give it a good clean.

Secondly, I didn't realize how much rubbish was forced to startup, even after a factory reset. So i disabled everything at startup. My memory usage at idle is now 1.6 GB (out of 4), before it was 2.2 GB.

However there's still some lag. If I'm using Chrome for a while, then click to expand the start menu it takes a second to register my pointer's position over 'buttons' (like computer, or music etc.). However the lag is not there if I then go between Chrome and the start menu every few minutes. Perhaps it is being stored in the RAM here, whereas If I were to use Chrome for a long while, then the start bar would be lost from the RAM hence take longer to load when I click on it.

But perhaps this is normal and I'm expecting too much from my mediocre nearly 5 year old laptop.

Does Dell also install lots of crap to slow their laptops down?

I've dealt with HP and Lenovo and they are notorious for almost halving your computers performance before shipping it to you. No idea why but it happens. Fresh HP laptop the other day, after bootup would just sit there thrashing the HDD loading about 30-40 completely unnecessary processes. Original Windows ISO and 30 mins later, the processes and RAM usage were halved and the laptop was twice as fast.

If Dell also does this then I'd recommend a clean install of Windows from an official Microsoft ISO, none of this manufacturer recovery crap.

Hard drives slow down over time, most users don't properly clear them out.

Slap in an ssd and uninstall the rubbish along with some compressed air on the intake and they perform better than new.

Meaker said:

Hard drives slow down over time, most users don't properly clear them out.

Slap in an ssd and uninstall the rubbish along with some compressed air on the intake and they perform better than new.

Click to expand...

One thing with mechanical HDDs used in laptops is that features like AAM and APM can cause it to be sluggish in responding to changes in activity levels which can sometimes be noticed as the mouse stalling for a moment or icons slow to load, etc. an SSD can definitely help there.