Cyberstorm PPC with Acard aec-7730A and samsung pro 850SSD

[mechy]

Hi all,
  Ii have been experimenting with the Acard aec-7730A lvd scsi to sata bridge on my amiga 4000 and have tested some firmwares as well as about 6 different cables.

setup: A4000 mediator tower with Cyberstorm PPC 128MB ram,Zoram 256,Deneb,radeon 9250,sb128,100Mbit ethernet.

I just purchased a 256Gb Samsung Pro 850 SSD for this.

I tried every combo of cables(5 different cables),and several styles of terminators from regular UW terminators to LVD/SE combo terminators.

Cables ranged from round w/twist,flat UWscsi cables,flat with twist,u160-twisted,u320 twisted. cables ranged from 24" long to 50" long(the max UWscsi can take).
With the CSPPC scsi in synchronous mode i am getting the following speed:

Diskspeed4.2:
Read: 31981560Bytes/s  (approx 31.9MB/s)
Write: 33259520Bytes/s  (approx 33.2MB/s)

Some notes on the Acard 7730:
With the latest firmware V1.73Q the ssd would show the correct size on the first hdtoolbox screen,but in the partition it would only show 21GB.

I reflashed the 7730a to the older 1.71Q firmware and it fixed this problem, the Samsung SSD shows the full size and partitioned out.

I am using SFS 0/0 on this setup with 2-2GBb partitions and 2-116GB partitions.

i have copied many files over as large as 2Gb and small ones and have not had any data corruption or problems so far. Experimenting with max transfer doesnt seem to change speed either or reliability.

Cable length and twist doesn't seem to matter at all. the 50" cable with 11 connectors works as well as the shorter ones. Termination is on a connector near the CSPPC side and i am using a old plextor 40x scsi cdrom drive as end termination.

Terminators i experimented with also showed no changes in speed and reliability.

Uwscsi standard calls for untwisted Ultra rated cables,but i find the lvd160/230 cables with twists are just as reliable.

The conclusion is the UWscsi on the Cyberstorm ppc rocks and is quite speedy. These figures are not much slower than i had attained with real UWscsi 15k drives.:knuddel:

I also tested the Acard 7720UW(i have run these for many years with dual 32GB sandisk cards rated 30MB/s, i was getting 29MB/s speeds.

[Oldsmobile_Mike]

Very nice system!  #jealous   :banana::banana:

[danbeaver]

Yep,  those numbers look dead on (mine are published on the Hyperion Classic forum). On a 15K U320 Atlas drive, I got about 35 MB/s in OS 3.9; OS4.1 was just a bit behind at 32 - 33 MB/s.  Your CF card numbers rock (I got from 23 to 26 depending on brand), but the SSD I tried was no where as near as nice as your Samsung, but the bus is so saturated one can't tell a Sandisk (mine) from a Samsung.

[mechy]

Yep,  those numbers look dead on (mine are published on the Hyperion Classic forum). On a 15K U320 Atlas drive, I got about 35 MB/s in OS 3.9; OS4.1 was just a bit behind at 32 - 33 MB/s.  Your CF card numbers rock (I got from 23 to 26 depending on brand), but the SSD I tried was no where as near as nice as your Samsung, but the bus is so saturated one can't tell a Sandisk (mine) from a Samsung.

The samsung 850 pro is way overkill for the amiga speed wise, but i bought it mainly for longevity, its MLC NAND and they have a superb reputation. i paid $149 for 256Gb which comes out way cheaper than a cf card of similar capacity. I bet that even the slower/older SSD's would still give good speed results. i was hoping to hit that magic 35MB/s spot with the SSD but the Acard 7730A is more than likely the limitation.

[danbeaver]

That was my conclusion in the forum post, as it has to take some amount of time due to the parallel-to-serial conversion.