This one not only mentions the Topaz XT GPU variants but also mentions the Amethyst XT which is the supposed codename of the R9 M295X.

Some more digging led to a very very interesting freebsd data dump.

The nomenclature previously occupied by Sun and Opal Pro/XT variants. It comes in three variants: Topaz Pro (R7 M255) Topaz XT (R7 M260) and Topaz XT (R7 M265). These are 384 Stream Processors with 24 TMUs and 8 ROPs. Apart from clock speed differences and a major difference in the noted launch date, both these GPUs have exactly the same specs. PCI Devices, who list preliminary machine identification information, yielded the same nomenclature and codename. Both of these GPUs were codenamed 'Topaz XT'. Searching TechPowerUps database brought me to the the mobile GPUs named R7 M260 and R7 M265. Or if its significant enough to warrant it, a new write up. The first thing I did when I started was fire off an email to AMD and as soon as they reply (if they reply), I will update this article. Because more often than not, it indicates a GPU that is just about to be released. This phrase 'preliminary support is added for xyz' is a very well known phrase to the aspiring hardware enthusiast. 'Preliminary support is added for AMD 'Topaz' GPU.' Seeing is believing, so the following is an extract (which can be found here): The first clue can be found in the changelog for the new GPUZ 0.8.0, which was posted online and supported a very enlightening detail. Since this entire affair is pretty chaotic, let me start from the beginning. AMD 'Topaz XT' codename surfaces in the wild - an OEM rebrand or a feature level 12 capable mobile GPU? It is also mentioned as a full fledged DirectX12 GPU, something which combined with the lack of any public data only adds to the mystery. Curiously however, this GPU is slated to be the R7 M255/R7 M260/R7 M265 a space which is currently occupied by an Opal Pro/XT chips. The mobile codenames of AMD, 'Topaz XT' has been spotted in the newest iteration of GPU-Z. Something pretty interesting came my way recently. Note: This is a highly exploratory editorial and while all sources are given, nothing in this write up is presented as the gospel truth for you to believe.

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