Dell W17C Guide D'installation Et De Caractéristiques page 18

Primary/Boot drive
1 x M.2 Drive
1 x 2.5 inch Drive
1 x 2.5 inch HDD with M.2 Optane
NOTE: Supports RAID 0 and 1 with M.2 SATA SSD and 2.5" SSD/HDD. RAID 0 and 1 are not supported with M.2 PCIe
SSD and 2.5" SSD/HDD due to different interface types. It is not available with Optane memory (Available from August
2019).
For optimal performance when configuring drives as a RAID volume, Dell recommends drive models that are identical.
RAID 0 (Striped, Performance) volumes benefit from higher performance when drives are matched because the data is split across
multiple drives: any IO operations with block sizes larger than the stripe size will split the IO and become constrained by the slowest of the
drives. For RAID 0 IO operations where block sizes are smaller than the stripe size, whichever drive the IO operation targets will determine
the performance, which increases variability and results in inconsistent latencies. This variability is particularly pronounced for write
operations and it can be problematic for applications that are latency sensitive. One such example of this is any application that performs
thousands of random writes per second in very small block sizes.
RAID 1 (Mirrored, Data Protection) volumes benefit from higher performance when drives are matched because the data is mirror across
multiple drives: all IO operations must be performed identically to both drives, thus variations in drive performance when the models are
different results in the IO operations completing only as fast as the slowest drive. While this does not suffer the variable latency issue in
small random IO operations as with RAID 0 across heterogeneous drives, the impact is nonetheless large because the higher performing
drive becomes limited in all IO types. One of the worst examples of constrained performance here is when using unbuffered IO. To ensure
writes are fully committed to non-volatile regions of the RAID volume, unbuffered IO bypasses cache (for example by using the Force Unit
Access bit in the NVMe protocol) and the IO operation will not complete until all the drives in the RAID volume have completed the
request to commit the data. This kind of IO operation completely negates any advantage of a higher performing drive in the volume.
Care must be taken to match not only the drive vendor, capacity, and class, but also the specific model. Drives from the same vendor,
with the same capacity, and even within the same class, can have very different performance characteristics for certain types of IO
operations. Thus, matching by model ensures that the RAID volumes is comprised of an homogeneous array of drives that will deliver all
the benefits of a RAID volume without incurring the additional penalties when one or more drives in the volume are lower performing.
When RAID is used for two non-identical drives (i.e. M.2 + 2.5 inch), performance will be at the speed of the slower drive in the array.
Audio
Tableau 6. Audio
Audio haute définition Realtek ALC3289 intégré
Prise en charge stéréo haute définition
Nombre de canaux
Nombre de bits/résolution audio
Taux d'échantillonnage (enregistrement ou lecture)
Rapport signal/bruit
Audio analogique
Waves MaxxAudio Pro
Impédance prise jack audio
Microphone
Entrée de ligne
Sortie de ligne
Casque
Puissance nominale du haut-parleur interne
18 Caractéristiques du système
Form Factor
1 x 2.5 inch Drive
NA
NA
Oui
2
Résolution 16, 20 et 24 bits
Prise en charge des taux d'échantillonnage 44,1 kHz/48 kHz/
96 kHz/192 kHz
98 dB pour sorties DAC, 92 dB pour entrées ADC
Oui
Oui
40K ohm~60K ohm
n.d.
100~150 ohm
1~4 ohm
3 W (moyenne) / 4 W (crête)