My ASUS ROG Strix RTX 4090 developed a vapor-chamber failure after roughly two years. ASUS and the retailer acknowledged it as a hidden defect, but after more than nine months in the repair process, the 4090 is no longer available. I was offered either a refund of the original 2024 invoice price or one of three 16GB RTX 5080 models: the ProArt RTX 5080, TUF RTX 5080, or Prime RTX 5080.
The refund is 92,000 Turkish lira, which is roughly the same as the current price of a new RTX 5080, but significantly less than the inflation-adjusted value of what I paid. A used RTX 4090 now costs around 200,000–215,000 lira, while an RTX 5090 is roughly 300,000–330,000 lira.
I mainly use the GPU for local AI models, CUDA workloads, and rendering, so VRAM capacity matters a lot. The 4090 has 24GB, while the 5080 has 16GB. From what I can tell, the 4090 is also faster in raw performance and compute in many workloads. Is the 5080 genuinely an equivalent replacement, or would it be a substantial downgrade for my use case?
3 Answers
Before accepting either offer, I would continue asking for a 24GB-or-larger replacement, a credit toward a 5090, or the original 4090 returned so the cooler could be repaired or replaced independently. A 5090 is not a perfect performance match either, but it is the only current consumer option with more VRAM. If none of that works, a 5080 is still a powerful card, just not an equivalent substitute for a 24GB 4090.
It is not an equivalent replacement, especially for local AI. The 16GB limit can prevent models from loading or force you to use offloading and other compromises, while the 4090's 24GB is a major advantage. Gaming performance may be relatively close depending on the title and features, but that does not make the cards equivalent for CUDA, rendering, or AI workloads.
That is the key distinction here: this is not just about average gaming FPS. Losing 8GB of VRAM can change which models and projects are usable at all.
If the actual choices are a 92,000-lira refund or a 5080 worth approximately the same amount, taking the 5080 is probably the more useful option financially. You could keep it, sell it, or use it while looking for a better solution. It still represents a downgrade, but the refund would not let you buy anything comparable in today's market.
I would choose the highest-end 5080 they will provide rather than the Prime model, then compare local resale prices. The ProArt or TUF version would at least be a better-quality replacement than a lower-tier model.
Since the original card reportedly still worked with reduced power and only needed cooling repaired, getting it back would be worth pursuing. A replacement cooler or water block might have preserved the 24GB card, although after nine months it may no longer be available.