My 2TB Rocket 4 plus (got it in 2021) write speed is only giving me 1800 write speed. Read speed seems ok at around 7000 though.
I've tried all sorts including what's below...
Running windows 11
Motherboard: Crosshair VIII dark hero
Rocket driver Firmware: RKT4P1.2
Latest AMD chipset driver: 7.06.02.123
Drive is in M.2_1
Graphic card in pciex16_1
Transfer Mode(crystal disk info): PCIe 4.0 x4 | PCIe 4.0 x4
Gen 4 set in bios for the drive and pciex16_1
Smart says health is good.
Temperature: around 40, has the heatsink.
Free space: 1.18 TB
There may have been a couple of other options in the bios i changed or were already what they should be, so I'm pretty sure it's not the bios settings.
It shouldn't be lane sharing either.
So i was trouble shooting with chatgpt and basically this is what it said once i exhausted all my options...
If the cache is full (or the firmware mishandles it):
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Writes skip straight to TLC → speeds drop massively.
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On a healthy Rocket 4 Plus, even “post-cache” writes should still be ~3,000–3,500 MB/s.
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On firmware RKT4P1.2, a bug causes it to sometimes fall all the way to ~1800 MB/s (exactly what you’re seeing).
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The cache should “empty out” when the drive is idle.
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If it doesn’t clear correctly, your very next write test starts slow.
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This can make it feel like the drive is always stuck at 1800 MB/s.
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So it sounds like a firmware issue when it mentions a bug, so is that firmware buggy?
