If your computer is starting to show its age, don’t throw it out—there are plenty of ways to get the performance you want out of your existing machine, or get a good deal on a trade-in. Here are some of the cheapest ways to upgrade your computer without risking your security or wasting money on a lemon.

1. Take your computer in for a deep diagnostic

If your computer is already struggling to handle basic tasks like word processing or web browsing after two or three years, it’s probably not a hardware issue—you likely have malware, or just bloated, unnecessary processes running in the background constantly, sucking up your computer’s processing power.

An up-to-date malware scanner should catch most threats (as long as you’re reasonably careful about where you go and what you download), but things like registry key infections will probably require a specialist. Find a technician you trust, and ask whether your computer ought to be able to handle the processes that it’s struggling with. They’ll help you find which programs (or malware) are slowing your computer down, and help you clean things up. A solid diagnostic shouldn’t cost more than $50-$75, and it can extend the usable life of your computer by a year or more.

2. Install extra RAM

RAM defines how many tasks your computer can handle at once, so if things start to get choppy when you have lots of tabs or applications running, popping in an extra GB or two of RAM can make an older computer run like a champ. For those intimidated by the prospect of “fiddling” with their computers, don’t worry—installing new RAM isn’t much more complicated than swapping out the batteries in your remote control.

The challenge is making sure your new RAM is compatible with the slots on your device—they’re not all alike, so consult an expert before buying. An extra GB of RAM shouldn’t cost much more than $25, and if you buy it from a repair shop, they’ll often install it for free.

3. Add a hard drive

Computers need free space to operate efficiently—most processes involve shuffling a lot of data around, and a computer that doesn’t have room to do so will start slowing down and experiencing errors. If your hard drive is consistently between 75% and 90% full, buying an external hard drive can really help your computer run faster.

For extra credit, you can install the hard drive inside your computer, but an external hard drive that plugs into a USB port will correct this problem just as easily. For around $50, you can pick up a 500 GB external hard drive that will probably be more than you need, unless you’re storing hundreds of high-definition movies on your computer.

4. Trade up

If salvaging your computer is more work than you want to put in, most computer repair shops will accept trades toward a new or used computer. This is probably the best option if you own a laptop, since they’re much more challenging to repair or upgrade. Many manufacturers also offer online discounts—check out this Lenovo ecoupon that slices hundreds of dollars off the sticker price. The only way you can go wrong, really, is buying from a big-box store—you’ll deal with insane markup and clueless support.

5. Recycle it

If your computer is so far gone that even the repair shops won’t take it, it still isn’t a good idea to throw it out—computers contain toxic chemicals and heavy metals that can leak out and poison groundwater, and landfills are also prime turf for identity thieves, who can resurrect your dead computer to steal personal information. Instead, take it to an e-waste processing facility, where it can be responsibly disassembled and reclaimed.