Optiplex Desktops

[LinhDell]

Hi Team,

I got a chart of Dell for SSD speed rate as below:

from here you can see the rate is calculated by K, so how can i convert it to Mb/s ?

Thanks

[speedstep · Accepted solution]

Class 10 vs 20 vs 30 vs 40 vs 50     2100K = 2.1 Meg

Posting Pictures Doesnt work All we see is a Triangle

The answer is not a one size fits all nor is it a sound byte.

Class	Sequential RW	Random  RW	Interface
10 Value	520K/320K	30K/10K	Sata
20 Mainstream	500K/300K	80K/60K	Sata
30 Performance	550K/350K	90K/75K	Sata
40 Performance	1500K/350K	200K/80K	PCI-E NVME
50 Performance	2100K/1200K	300K/100K	PCI-E CARD X4

Sequential = Boot, hibernate,  daily power up and down

Random = tasks such as file search:KIOPS

Typical SATA 2 speed is 250K

Typical SATA 3 speed is 500K

The faster speeds are usually 2 NVME drives in parallel RAID 0

X16  PCI-E cards can Get 8000K sequential speed.

https://www.seagate.com/files/www-content/datasheets/pdfs/nytro-5910-nvme-ssdDS1953-3-1801US-en_US.p...

 Sequential Read (MB/s) Sustained, 128KB                        8,150,000
Sequential Write (MB/s) Sustained, 128KB                          4,800,000
Random Read (IOPS) Sustained, 4KB QD64                          975,000
Random Write (IOPS) Sustained, 4KB QD64                          132,000
Random 70/30 R/W (IOPS) Sustained, 4KB QD64                  369,000

[LinhDell]

So it means for example:

20 Mainstream

500K/300K

-> The sequential rate is ~ 0.5Mb/s / 0.3 Mbps ?

Thanks

[speedstep]

Yes thats the typical SATA 3 speed for onboard controller.   Faster requires Raid where more than one drive at a time is running and typically  X2 X4 X8 X16 PCI-E.

Apricorn Velocity Solo X1 card is 500K max for example.

The Serial ATA (SATA) interface was designed primarily for interfacing with hard disk drives (HDDs), doubling its native speed with each major revision: maximum SATA transfer speeds went from 1.5 Gbit/s in SATA 1.0 (standardized in 2003), through 3 Gbit/s in SATA 2.0 (standardized in 2004), to 6 Gbit/s as provided by SATA 3.0 (standardized in 2009)

https://www.bhphotovideo.com/c/product/887344-REG/Apricorn_vel_solo_x1_Velocity_Solo_x1_SSD.html

PCIe 2.0 x1 slot with two SATA III (6 Gbps)

(backwards compatible with PCIe 1.0 x1 slot and SATA II & I)

[Tesla1856]

Can't see your pic, but typically you divide by 8 (8 bits in a byte).

[DaveyBR]

If anyone is interested I benchmarked my Dell Class 35 (mainstream) 128GB NVMe drive in a 3070 micro and got the following:-

It's definitely faster than a SATA SSD but also noticeably slower (higher latency and lower throughput) than top end NVMe drives I've used.

Full model number = KBG40ZNS128G NVMe KIOXIA 128GB and it uses Toshiba NAND chips.

[ScottyHTS]

Class-35 appears to be DRAM-less SSDs, likely using QLC chips.  Tehy are PCIe, gen 3, and likely top our around the ~2200MB/s in the 512GB/1TB versions.