I lost ya on the last sentence? The other selection in Chrome?
The option on the bottom where it says 'Use hardware acceleration when available'. It's OK to leave that one checked, to make Web pages look better. Note that this may or may not make any difference on some computers, if not, uncheck it also. Many will receive some benefit.
It's right below the option to 'Continue running background apps when Google Chrome is closed'. No way to miss it.
Hope this makes my prior post more clear.
Though for the best bang of performance for the buck, as long as your computer has a 2.5" SATA HDD, grab a 120GiB $50 SSD on promo from Newegg, you want some speed, you have it!
However I recommend that more for your HP than the Acer. Modern Linux distros can make the needed adjustments on SSD's w/out the need for GParted, just use the regular install process to create partitions. Make sure to leave 10% of unused space at the far end of the SSD, this makes it perform better & increases lifespan. Most of mine, I have 20% unused reserve space for this task.
This isn't a Free solution, however if one wants a faster computer, some cash has to be spent, and SSD's are the best 'bang for the buck' at this time. Remember when you increased your RAM in the HP to 4GB total, how much faster it became? Well, a SSD will provide a more noticeable impact. Though I recommend to stay away from the Kingston SSDNow V300 value series line, the ones in the red packaging, way too many negative reviews for me to consider this purchase, though there are other low cost options in the 120 through 128GiB sizes. Sometimes, one can get a 250 to 256GiB model for as low as $80 on promo of the Samsung of Crucial brands, both of which are highly reliable. And quick as a cat.
My last spinners are on pre-2010 model computers, only one isn't by choice, I have a couple of extra extra SSD's, it's just that two of the models are SATA as far as plugging in goes, but are enhanced IDE ports, though someone is assisting me with an add-on SATA card that I have for one of the two (HP dc5800). The other is an IDE based notebook & the oldest that I have. Have an Dell Optiplex 740 where it 'may' be possible to have some form of true SATA, by activating RAID in the BIOS. If there's only one drive installed, it should be seen as a true SATA connection, though at SATA-2 speeds (same with the HP).
While there are many Free 'speed me up' tips & tricks, the sure fire way for speed & power is investing a little in hardware for the purpose. That HP of yours would fly with a SSD, and maybe the Toshiba also. The Acer may also benefit, if it has a SATA HDD installed. Crucial has a scanner for compatibility, though you don't need to purchase from them. A 2.5" SATA SSD is not locked to a model, like RAM is. Note that some computers requires a 1.8" model, though these are more rare, some Toshiba models has this size drive installed.
You must look at all of your options to get the best speed from a computer, not just software tweaks. I'm just telling it like it is, have been down this path years ago of trying to make low-spec computers faster.