I know this thread is old but someone along the way said you cannot upgrade the hard drive in this laptop and that is incorrect. Sure, you have to dismantle the chassis to get at the hard drive, but it is certainly upgradable in this unit.
I have the exact same laptop, and I dropped in a 525 GB Crucial SSD and an 8GB 1600 Crucial DDR3 stick. $10 for an enclosure and I got a nice 1TB external USB 3.0 drive out of the deal.
I actually get VERY playable frames in a lot of games. Anything Source engine runs between 50-60FPS on medium-high settings. Rocket League averages 40-60FPS on medium settings. DiRT 3 and GRID Autosport run BUTTER smooth on high. Hell, I even get about 25-40fps in Overwatch on low settings. Not the most playable, but it works in a pinch. Please keep in mind this is running at the screens lackluster 1366x768 native resolution so that certainly helps the FPS. When I connect it to my 50in 1080p TV it's a whole different ball game. However, some of the above are still very playable, albeit not nearly as smooth as one would want them to be.
The ram upgrade gave the integrated graphics a lot more to play with, and the SSD changed everything. Virtually instant boots and a noticeable improvement to frame rates. I know that the general consensus is that they'll only improve loading time, and that was certainly the case in my desktop, zero frame improvement as expected, but I was pleasantly surprised to notice the boost after swapping out the drive. I believe they can definitely help frames when you're putting them into what started out as such a weak system. Now it feels like 6 or 700 dollar laptop for a fraction of the cost.
I picked up this laptop on Walmart clearance brand new (the stuff they keep out back, not advertised you have to ask for it.) For $140 w/ Windows 10 Home. Popped in the above upgrades, and now for under $300 I have an i7 (given its a U series) laptop with 12GB of DDR3 and a 525SSD, dual booted with Ubuntu.
Absolutely love it. Bought it for coding, but never imagined a few cheap upgrades would improve it as much as it has, and I've been in IT professionally for 10 years, and building gaming PCs for almost twice that time.
TL;DR: I wondered the same thing about a potential PCI-E expansion slot as I also saw the upgraded versions of this laptop touting dedicated graphics. I haven't fully pulled the motherboard out, but plan on doing so to replace the heatsink compound with some good stuff at some point, and then I'll know for sure. However, upgrading the SSD and Memory to their max make this a great little laptop for the price.