Do GPU Riser Cables (Extension Cables) Reduce Performance?

PC cases are getting smaller at a time when GPUs keep getting bigger, often resulting in people needing to buy GPU riser cables to squeeze everything into their PC build. But if you’ve started having bad performance or FPS rates, you might be wondering whether your riser cables are to blame. Let’s dig into whether they can reduce performance or not.

Recap: What Are Riser Cables?

PC hardware is rapidly approaching a point where we can’t eke out more performance from the same size transistor (leading people to ask whetherMoore’s Lawis dead). As a result,graphics card makershave started making them a ‘bit’ bigger instead:

The GeForce RTX 4090 is bigger than the Xbox Series S… and the Series X, the Steam Deck, and the Nintendo Switch 😅https://t.co/B5QaGUlXoFpic.twitter.com/04UBuoOJIh

Yes, NVIDIA’s flagship RTX 4090 GPU is actually bigger than entire gaming consoles! This presents a problem for PC builders, because we don’t all have room for massive cases. Heck, even bigger cases like the Lian-li O11DXL canstruggle to fit the RTX 4090– which seems a bit crazy to me.

One solution to this growing problem is to buyPCIe riser cables, also sometimes called PCIe extension cables. These allow you to move the location of your graphics card, which otherwise would have had to be installed in your motherboard’s PCIe slot and then attached to a certain point of your PC case:

That’s where PCIe riser cables come in – they plug into the motherboard’s PCIe slot, and then allow you to move your GPU to another place (you can ‘rise’ it above the original slot):

Can These Extension Cables Reduce Performance?

In general, a high quality PCIe riser cable will not impact GPU performance at all. However a low quality PCIe extension cable might cause issues, as will using a PCIe 3.0 riser cable with a modern PCIe 4.0 graphics card. People also sometimes blame riser cables even though other issues or bottlenecks are the actual cause of poor graphics performance.

That’s the high level answer, but let’s dive into the detail a bit more – especially because PCIe can be a confusing topic, because you have to consider:

This is an important point, because thefollowing riser cablewilldefinitely harm your performance if used with a modern GPU:

While there’s nothing specifically wrong with that riser cable (i.e. I assume it’s a high quality and well built cable), the fact that it’s a PCIe 3.0 cable and it only uses one PCIe lane (“X1”) means that it will inherently limit the performance of a modern GPU that is almost certainly PCIe 4.0 x16.

That particular riser cable is probably designed to reposition an older PCIe 3SSD, and not a high performance GPU.

Key Point:You should always ensure that the PCIe riser cable you use matches the PCIe generation andlanes of your graphics card. For example if you have an RTX 4080 (which is PCIe gen 4 and runs at x16), you will need a modern PCIe 4.0 x16 riser cable – otherwise the riser cablewilllimit your graphical performance.

Secondly, if you purchase a really budget, no-name PCIe extension cable then there’s no guarantee that it will run at the stated performance. Not to hate on AliExpress, but can you say for sure that these cables are all 100% performant?

I don’t mean to bash AliExpress (they can be a great resource for certain equipment), but some of the PCIe riser cables they sell have minimal (or zero) reviews – and they haven’t undergone extensive third party testing. So even if you do purchase a “PCIe 4.0 x16” cable from there, you can’t be completely sure that it will run at the stated speeds/specifications.

If you have an expensive GPU, I would always purchase a quality PCIe riser/extension cable from a reputable online retailer (which also excludes Amazon, whohave a growing problem with fake products). Companieslike LINKUP, Lian-li and Thermaltake all produce good quality riser cables, but naturally always double check the reviews for the specific product you plan to purchase.

Side Note:If you’re interested in learning more about the performance of riser cables, there wasan awesome post on the Overclock forumthat did quite detailed testing on five riser cables of varying length and quality. In their testing, there was barely any performance difference between using riser cables or not. Some people also say that unshielded cables can cost performance over a certain distance, but their testing didn’t conclude this either.

Factors That DO Affect Graphical Performance

So we now know that if you are experiencing worse graphical performance, it’s unlikely to be caused by your riser cables. But whatcanbe causing the performance drops? Well this topic could be an entire article in itself, but the most common things to check are:

Related Reading:30 Awesome PC Games That Run Smoothly With Just 4GB Of RAM

Tristan has been interested in computer hardware and software since he was 10 years old. He has built loads of computers over the years, along with installing, modifying and writing software (he’s a backend software developer ‘by trade’).Tristan also has an academic background in technology (in Math and Computer Science), so he enjoys drilling into the deeper aspects of technology.Tristan is also an avid PC gamer, with FFX and Rocket League being his favorite games.