I have a GoFlex 1TB 3.0 USB external HDD that I was using on my windows 7 laptop via a expressslot USB3.0 adapter. With the Windows 7 policy of "optimize for performance" to enable write caching I was able to achieve upwards of 125mb/s sequential write rates (I do video recording so that's the only metric I really care about.)
On this Windows 8 asrock z77 pro 3 computer I'm getting 25mb/s sequential write rates no matter if I use a USB3.0 or a USB2.0 port. I can't figure out what the issue is.
In UEFI I disabled USB3.0 legacy support.
In "Seagate FreeAgent GoFlex USB Device Properties" I have Removal policy set to "Better performance" - however, if I try to enable "Write-caching policy" it gives me this error: "Windows could not change the write-caching setting for the device. Your device might not support this feature or changing the setting."
I'm not really sure what the Windows 7 equivalent is between the options, but I'm assuming it's both. I have tried using asrock's z77 pro 3 windows 7 USB3.0 drivers but they wouldn't install due to compatibility concerns.
I can downgrade to Windows 7 and I'm sure it would work, but I'd rather not as Windows 8 is more performant over-all.
It's apparently the software I used on Windows 7 that has been updated to Windows 8 - by chance of luck I just stumbled onto it after I made a public post (..) after searching for it for a few hours earlier. Well, I'll report back if this fixes it!
EDIT: No big surprise, that didn't work either.
EDIT: I'm getting this message "Device can preform faster when connected to USB 3.0" in the details pane of the external HDD. But it's connected to a USB 3.0 port. I don't understand. I think it has something to do with the default Windows 8 USB 3.0 drivers not working correctly ><
"You are using a USB 2.0 hub.
If you are using a hub, verify that it's a USB 3.0 hub. If you're using a USB 2.0 hub, any attached SuperSpeed USB device will operate at high-speed. Either replace the hub with a USB 3.0 hub, or connect the device directly to the USB 3.0 port."
In my device manager I can tell that the ext. HDD is connected to one of my two "Generic USB Hub"'s -- Down the list there is a USB Root Hub (xHCI) but if I check it - it has no devices connected. Since that's the only USB 3.0 hub I'm thinking the USB 3.0 port is perhaps connected to the wrong hub? Then again it says "Generic USB Hub" so maybe this doesn't really mean much as to which Root hub it's connected to. Once again however I am stumped. Help would be appreciated!
Okay The Generic USB Hub the ext. HDD is connected to says "Hub is operating at high speed" - which is USB 2.0 speed, NOT USB 3.0 super speed. Both of the Generic USB Hub's are operating at high (USB 2.0) speed. This appears to correspond with the two USB Root Hubs that are also operating at high speed. The USB Root Hub (xHCI) properties tab does not have a Power or Advanced tab - maybe it's just not been connected? I'll open up the Case in a bit and look.