Let’s talk about Nvidia’s RTX 3080 CTD Issues – Are SPCAPS and MLCCs to blame?

It should be common knowledge now that some RTX 3080 users are experiencing stability issues, seeing users of Nvidia’s latest Ampere products crash to desktop (CTD) when playing certain games at high clock speeds. 

Note that this issue does not impact all RTX 3080 graphics cards. Reports of stability issues have come from various sources and affect a range of custom RTX 3080 designs. Right now, we know that these RTX 3080 stability issues cannot be blamed on a single manufacturer or GPU model, making these stability issues a lot harder to diagnose than many realise. 

These stability issues are not a universal problem, so don’t expect all RTX 3080 graphics cards to face stability issues. 

What’s the problem? Why are RTX 3080 GPUs crashing?

The problems facing some RTX 3080 users sit firmly within the realms of electrical engineering. To say that modern graphics cards are complicated is an understatement, and we do not have the expertise to explain the RTX 3080’s stability issues in great detail. Even those with degrees in electrical engineering will tell you that the power delivery circuits within modern computers is an incredibly complex field of study. 

The CTD issues facing Nvidia’s RTX 3080 graphics cards can be pinned on power delivery, but saying that alone oversimplifies the matter. There are so many factors that can impact GPU power delivery, blaming a single component or factor is unhelpful. While much of the conversation surrounding these issues have come down to SPCAPS and MLCC arrays, there are other factors at play. 

Igor’s Lab has written an excellent piece describing the electronics behind this issue in great detail. However, we will note that factors can impact power delivery outside of capacitor selection. The stability of your power supply is a factor, the power circuitry of your graphics card is a factor, the intended clock speeds of your graphics card is a factor and so are Nvidia’s Geforce drivers and the quality of your Ampere GPU’s silicon. 

While most of the conversation surrounding this issue is focused on SPCAPS VS MLCC arrays, remember that these other factors matter. 

Are SPCAPS to blame? 

Recent statements from Nvidia board partners like EVGA have implied that POSCAPs/SPCAPS can be blamed for RTX 3080 stability issues. On their Forums, EVGA has confirmed that “a full 6 POSCAPs solution cannot pass the real world applications testing” for their custom RTX 3080 models. The implications of this are that SPCAPS are not good enough to supply Nvidia’s RTX 3080 with clean power, but the matter is a lot more complicated than that. 

Remember that there is no single SPCAPS or MLCC chip that GPU manufacturers use. Manufacturers can select from thousands of different chips depending on their power requirements. Each of these chips have different power characteristics and are therefore best suited to different applications. Some GPU manufacturers may have selected better SPCAPS or MLCC chips for their chosen tasks, making component selection a vitally important aspect of product design. 

Depending on the chips that Nvidia’s AIB partners have selected, some RTX 3080 designs may face more issues than others. That said, RTX 3080 GPUs which use more MLCC chips appear to be more resilient to RTX 3080 stability issues. Other design elements of graphics cards will also have their impact, as will the quality of your GPU’s silicon. 

Things are a lot more complicated than you think!
 
Not all graphics card silicon is created equal. When transistor sizes are measured in nanometers, it is understandable that the chips within all modern graphics cards and processors cannot be manufactured with complete uniformity or without any defects. Some chips will require more power than others, while some will be able to run at higher core clock speeds when pushed to their limits. These factors have a part to play for these RTX 3080 stability issues, as more power-hungry RTX 3080 chips will place more strain on the graphics card’s power circuitry at high clock speeds, potentially causing these CTD issues.

Some RTX 3080 users with supposedly sub-par 6-SPCAPS configurations could face no issues if the quality of their RTX 3080 silicon is high enough, while those with more power-hungry chips could face issues despite using supposedly stronger MLCC arrays. Several factors are at play here, and the problem can be blamed on several factors depending on how you look at the situation.     

Software can also play a role in these issues, as Nvidia AIB partners informed us that Nvidia planned to increase RTX 3080 stability with a new driver update. Now, Nvidia has released its Geforce 456.55 WHQL driver which “improves stability” of RTX 30 series graphics cards. Both software and hardware play a role when it comes to hardware stability. 

Where does the blame lie? 

As we have stated before, the blame for RTX 3080 stability issues can be blamed on a number of factors. Pinning these issues on a single company or decision does a disservice to everyone involved, given the complexity of these products and how several factors impact both GPU performance and stability. 

Perhaps Nvidia has been too aggressive with the RTX 30 series’ power and frequency targets, as small underclocks have eliminated the RTX 3080’s crashing issues for many consumers. On the other hand, Nvidia could have given its AIB partners more time to put their designs through quality control; or have given them access to their full driver stack earlier so that real-world applications could be tested at an earlier date. 

Several aspects of Nvidia’s RTX 30 series launch appear to be rushed, and this has created time constraints which have allowed problems to fall under the radars of several GPU manufacturers. Igor’s Lab has claimed that Nvidia didn’t give their AIB partners full access to “suitable drivers” at an early enough stage to enable full QA testing for their custom PCBs. More extensive QA testing could have prevented these RTX 3080 stability issues entirely.