Upgrading current system - best upgrades on a budget?

katz103

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Sep 1, 2017
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I'm a total newb when it comes to computers, so please be gentle. I currently have an Acer Aspire desktop, model ATC-220-ES51. Junk, I know. I don't have a big enough budget to buy everything at once and build from scratch. Therefore, I'd like to upgrade one component at a time in this crappy machine, which would be easier on my finances, all while keeping in mind that eventually, all upgrades will hopefully make a pretty decent system (if possible).

I don't game much, although I do play WoW every once in a while. It crashes most of the time, giving me a BSoD, within 15 minutes of launching the game, and even on low settings, it's quite laggy. Other than that, I process pictures with Lightroom and Photoshop, which aren't all that fast either. I'd like to at least be able to run those three at a comfortable speed.
My budget for the first upgrade is no more than $500. What would you suggest I upgrade first, and what do you suggest I upgrade with?