The Eternal PC Question: Is It Better to Upgrade or to Buy a New Syste

A lot has changed in the PC market over the past few decades, but one question remains timeless: “Can I squeeze more performance out of the system I’ve got now, or do I have to build or buy something else?” Here, we’ll break down the issues in play and discuss how to make this decision in a way that gives you the best chance of maximizing your performance per dollar.

Laptop or Desktop?

Laptops, especially modern high-end systems, have far fewer upgrade options available than desktops do. Oftentimes the only things you can plausibly upgrade on a laptop are the system RAM, possibly the internal storage, and the cooling solution via the addition of an aftermarket laptop cooler. These are all useful in situations we’ll discuss below, but desktops have far more flexibility where upgrades are concerned.

PC Components Do Not Age at the Same Rate

The Core i7-2600K is older than the GTX 680, but CPUs age less quickly than GPUs do. 2GB of RAM doesn’t cut it very well these days.

This can be a good thing, from an upgrader’s perspective — it means that your CPU and motherboard platform tend to live longer and can be improved by the addition of faster graphics cards, for example.

Gaming Is Not Like Other Workloads

Games are an excellent way to test system stability and reliability, but gaming results generalize poorly to other applications. Specifically, games are often fairly insensitive to both CPU core count and CPU clock speed. A game may show a significant performance improvement moving from a dual-core CPU with Hyper-Threading (2C/4T) to a chip with four actual CPU cores (4C/4T), and its frame rates may improve modestly with clock speed, but there are very few games that show significant benefits when running on eight or 16 cores instead of four, and the improvement from playing at 4.5GHz compared with 3.2GHz may be far smaller than the 1.41x difference in clock speed. The gaming-specific benchmarks from our Ryzen 7 3000 review in June are shown below. Gaps between the various CPUs are smaller than in our non-game tests, particularly above 1080p.

In Ashes, the 9700K takes pole position, with the other Intel CPUs not far behind. The 3700X is 1.08x faster in 1080p than the 2700X. The gaps narrow as resolution rises, but the 9700K wins overall, with the AMD chips still a bit behind Intel at 4K.

DXMD shows the not-uncommon scenario of complete gridlock in a GPU-bound game. This is an effective tie across the board.

Hitman is a game where the 3700X picks up a solid 1.16x over the 2700X at 1080p. Intel retains a technical advantage (and the 9700K notches up another win), but the gap begins to collapse at 1440p and is gone by 4K. Gamers seeking to exploit every single frame may still prefer Intel in games like this, but the distance between them is fast disappearing.

By our 4K setting, Metro is being rendered at 8K internally, which is why it turns into a 30fps title. Intel's narrow 3 percent lead at 1080p is within a technical margin of error. Past that, the game is completely GPU-bound.

Shadow of War is another game where the Ryzen 7 3700X picks up a few frames on the 2700X, but doesn't quite close the gap with Intel. Just keep in mind, the difference between 130 and 139 fps is literally invisible to the naked eye.

In RotTR, AMD picks up a solid 1.08x over the 2700X, with the Core i9-9900K less than 4 percent ahead. The Core i7-8086K and the Core i9-9900K can't quite open a 5 percent lead. At 1440p the gap between the players is negligible; at 4K it's nonexistent.

The Ryzen 7 3700X delivers an astonishing 1.2x improvement in Warhammer II, effectively matching both the 9700K and 8086K. It keeps pace with both Intel CPUs at 1440p before the tyranny of 4K lays all silicon low.

SotTR just isn't particularly CPU-bound, even at 1080p. The gap between the 9700K and the Ryzen 7 3700X is just 2.5 percent. At higher resolutions, the game is completely GPU-bound.

CPU performance absolutely matters in gaming, but games do not scale to match CPU core counts the way well-threaded applications do, and they typically do not scale with core speed the way a single-threaded application would above certain minimum thresholds. People who mostly game can divert more of their upgrade funds towards the GPU-side of the equation, while those of you running extensive CPU workloads would want to focus money there.

Understanding RAM Upgrades

If you have 4GB of RAM in a system and your system never collectively needs more than 3GB, then bumping up to 6GB will not provide a noticeable benefit. If you have one application that requires 6GB of RAM and running it with just 4GB causes heavy file paging, then that specific application will benefit enormously from more RAM, while the rest of your applications may perform just as they did before.

RAM clock speed upgrades are almost never worth investing in unless you’re getting the clock upgrade incidentally. If you have 4GB DDR3-1066 and you buy 8GB of DDR3-1600 as part of an upgrade, that’s scarcely a bad thing, but if you have 8GB of DDR3-1066 I wouldn’t bother investing in 8GB of DDR3-1600. Most desktop applications are not particularly RAM-bandwidth bound. There is no need to update a DDR3 PC with acceptable performance to DDR4 just because of DDR4.

I’d consider 4GB of RAM to be the minimum you’d want these days, 8GB is reasonable, and 16GB would cover absolutely everything except for corner cases that you likely know if you need to cover. While I definitely don’t recommend blowing a lot of money on old RAM for a low-end system, the good news is that RAM is generally pretty cheap right now, and upgrades may not cost you much.

Can You Identify a Bottleneck?

In this context, a bottleneck is not an issue that’s preventing you from reaching maximum performance. Maximum performance is assumed to be out-of-reach without buying new hardware. The question is whether we can find a way to bring a system up to acceptable performance for a reasonable amount of money.

If you’re considering whether to upgrade or buy new, the first question to consider is whether or not you can identify a meaningful bottleneck in your current system. Compare the specs of the system you currently own with the recommended specs in the game or target applications that aren’t running well. If you aren’t sure how to compare the specs, Google product names and check the year when a given product was released. If a game requires a GPU that was released in 2015, and you have a GPU from 2012, you may well have found your problem.

This philosophy also can apply to OEM desktops. While I’m not making any specific system recommendations, it’s sometimes possible to find basic desktops with solid components that only need a GPU to be turned into gaming systems. Sometimes, these basic rigs are cheaper than the cost of buying all-new components yourself. Building the base system and tossing a midrange GPU into one can be a great way to get a gaming system without spending much money.

What If the Bottleneck Is Everything but the Motherboard?

Let’s look at a different twist on the same system configuration. Instead of a high-end rig, let’s examine a Core i3-2100 paired with a 2TB 7200 RPM HDD, 450W PSU, 4GB of DDR3, and a 1GB GTX 650, on the same Sandy Bridge motherboard from 2011 – 2012. This person still has upgrade options, but they are going to be more constrained in what they can expect without spending significantly more money. A GPU upgrade will absolutely still improve gaming performance, but the relatively low-end Core i3-2100 is going to drag on the improvement compared with a Core i7-2700K (there’s a breakpoint in many games between the Core i3 in a 2C/4T configuration and having a full quad-core). 4GB of DDR3 is low, so that needs to be upgraded. The power supply is big enough to allow for a modest GPU upgrade, but you wouldn’t want to drop a high-end card on a 450W PSU.

When you say “older systems,” exactly how old are we talking?

There’s no way to replace 1-2 components and bring a system like this up to modern performance levels, so you’ve got two options: Upgrade the most pressing bottlenecks (RAM and GPU for gaming, HDD for general I/O) but accept that the end experience still isn’t going to be great. A new Sandy Bridge CPU from Intel is quite expensive at this point.

Alternately, you could turn to used parts for more meaningful improvements and less money spent. Pre-owned chips like the 2600K are going for $45 on eBay, and that’s substantially less than you’d pay for an equivalent Intel CPU brand-new. In a situation where you need faster hardware but can’t afford to pay for all-new components, used hardware can fill those gaps.

In a case like the one I’ve laid out, a buyer might grab another 4GB of RAM for ~$15 (Newegg), a used CPU for ~$45, and up to an RX 570 for ~$130. Swapping a small SSD into the system is also possible, though the chore of slimming a 2TB Windows installation down on to an SSD is beyond the scope of this article.

If you aren’t willing to buy used hardware, it’s not going to be worth it to try and find a compatible Sandy Bridge or Ivy Bridge chips new. Even the Core i3-2100 I’ve used in this example still sells for $116 on Newegg.

Motherboard Bottlenecks

The first two scenarios I’ve laid out are fairly easy. Let’s say you’re stuck with a Core 2 Duo, AMD Phenom / Phenom II, or a modern Bulldozer / Piledriver-based system. Even in these cases, hitting the used CPU market might help — if you have a very low-end chip from the original families — but it’s unlikely to solve your problem because you’re starting from so far behind. In these cases, motherboard compatibility is going to be your major stumbling block, and swapping out the motherboard is really where you start to move from “upgrading” a PC to “building a new PC.” Because newer boards typically support newer CPUs and different memory standards, swapping a motherboard typically means swapping other components as well. Your operating system and other software may also insist on reauthenticating if you install a different motherboard.

There’s not much that can be done to ‘modernize’ an outdated motherboard. Some features, like M.2 support or USB 3 ports, can be added to a system via PCIe cards. But if you are fundamentally limited by CPU performance, that’s going to have to be dealt with — and that’s probably going to mean replacing your RAM as well.

Options for increasing CPU core counts are also limited. Moving from a Core i3 (2C/4T from 2011 – early 2017) to a desktop Core i7 (4C/8T through early 2017) will increase performance on the Intel side, but buying used is probably the only way to make it economical. If you’re still using Bulldozer or Piledriver parts, I’d just recommend saving for Ryzen rather than trying to boost your current CPU performance. Some modern Ryzen systems introduced since 2017 will be capable of stretching from 8 cores at launch to 16 cores once the now-delayed Ryzen 9 3950X eventually debuts, but this is a recent development. Some X58 owners from a decade ago may have the option of moving up to six-core chips, especially if your motherboard supported Xeon processors, but again — you’ll be hitting the used market for parts.

The motherboard, in other words, is the component most likely to force you into a replacement cycle rather than being able to make do with an upgrade — and it’s very difficult to future-proof systems or guard against that. The good news is, most people don’t need to replace their CPUs very often these days.

Rules of Thumb

It’s probably not worth investing in any attempt to upgrade a system running DDR2 or below unless you’ve assembled it specifically for legacy software.

4GB of RAM is enough for a lightweight system, 8GB is reasonable, 16GB covers all but the corner cases.

If you decide to upgrade a CPU, make certain that the cooler you own is compatible with the higher-power chip. Lower-end CPUs often ship with weaker coolers. Reasonable coolers are not terribly expensive, but if you buy a used chip without one you’ll need to factor that into the price.

Intel systems typically have weak CPU upgrade prospects due to motherboard limits. AMD CPUs prior to 2017 have weak upgrade prospects due to weak overall performance. In some cases, it may still be worth upgrading from a low-end chip (Celeron, Pentium, FX-4100) to a high-end core (Core i7, FX-8350) of the same generation. This will only be true in the most cost-constrained scenarios, however. In most cases, the end-user will see better results from saving money for a CPU + motherboard upgrade.

GPU upgrades are an excellent way to breathe new life into a gaming system. Make certain your power supply meets the requirements of the new card you are considering. A gaming PC can typically be considered reasonably high-end for 4-6 years if you simply keep the GPU updated.

If you have to swap a motherboard, it’s often a good idea to consider rebuilding the system from scratch. It’s much easier to switch motherboards without your OS catastrophically failing than it used to be, but the overall hassle of this issue is often the line between “starting over” and “upgrading what I have.”

Swapping out a motherboard is where an “upgrade” becomes a “rebuild” in my own opinion because this is where you have to start making more changes to the OS.

When Is It Better to Buy New or Build From Scratch?

The two things you want to keep an eye on when considering which route to take is the amount of hassle you’re willing to put up with and the difference in price. Some CPU coolers bolt to the board from the back. Some cases lack cutouts to make it possible to remove the cooler without removing the motherboard. Your case may be smaller than average or a serious pain to work inside of. You may have medical issues that make it more difficult to perform these sorts of improvements and no one around to help with PC upgrades.

You’re probably not going to save this one. Image credit: Wikipedia

If you already know how to build a PC and are comfortable doing so, the “upgrade versus rebuild” question is pretty straightforward for you. If you’re considering buying a new laptop or a boutique PC, my best advice is to read reviews of the models you’re considering. Ideally, you would then look for reviews of the specific PC you already own or a model that’s similar to it. If you care about gaming, just try to find benchmarks that focus on your GPU — that’ll get you in the ballpark. Compare the performance delta between what you’ve got and what you might purchase, and ask if the gains are worth the cost. Some people prefer to buy boutique systems because they prefer to spend time doing other things and don’t want the hassle of futzing around with parts. Don’t be afraid to price that into the equation.

If you start considering an upgrade project, realize that you’re now replacing 80 percent of the system, and just don’t want to deal with the headache — that’s a good time to just consider starting over. People shouldn’t be afraid to tackle upgrades but there’s nothing wrong with deciding you prefer the simplicity of buying a new system or paying someone else to build you one.