Inlet Temperature versus Airflow Requirement in Server
The following tables provide the required airflow
rate and airflow speed to the card under various operating conditions.
Note: In the following tables, the term load refers to
the total thermal power dissipation of the card.
Table 1. Required Flow at Sea Level for an Example 180W Load for 70°C Rated
QSFP
| Inlet Temperature
versus Airflow Requirement of PCIe Card Slot (34.8 mm x 106.65 mm) at Sea Level for
70°C Rated QSFP |
| Inlet Temperature to the Card (°C) |
Linear Feet per Minute (LFM) |
Cubic Feet per Minute (CFM) |
Pressure (inwg) |
| 5 |
300 |
12.0 |
0.15 |
| 10 |
320 |
12.8 |
0.17 |
| 15 |
350 |
14.0 |
0.19 |
| 20 |
390 |
15.6 |
0.23 |
| 25 |
440 |
17.6 |
0.28 |
| 30 |
500 |
20.0 |
0.35 |
| 35 |
570 |
22.7 |
0.44 |
| 40 |
660 |
26.3 |
0.57 |
| 45 |
750 |
29.9 |
0.71 |
| 50 (not supported) |
870 |
34.7 |
0.93 |
Table 2. Required Flow at Sea Level for an Example 180W Load for 85°C
Rated QSFP
| Inlet Temperature
versus Airflow Requirement of PCIe Card Slot (34.8 mm x 106.65 mm) at Sea Level for
85°C Rated QSFP |
| Inlet Temperature to the Card (°C) |
Linear Feet per Minute (LFM) |
Cubic Feet per Minute (CFM) |
Pressure (inwg) |
| 5 |
220 |
8.8 |
0.09 |
| 10 |
230 |
9.2 |
0.10 |
| 15 |
250 |
10.0 |
0.11 |
| 20 |
280 |
11.2 |
0.13 |
| 25 |
310 |
12.4 |
0.16 |
| 30 |
350 |
14.0 |
0.19 |
| 35 |
390 |
15.6 |
0.23 |
| 40 |
450 |
18.0 |
0.29 |
| 45 |
520 |
20.8 |
0.37 |
| 50 (not supported) |
600 |
23.9 |
0.48 |
Table 3. Required Flow at 1200m above Sea Level for an Example 180W Load for 70°C
Rated QSFP
| Inlet Temperature
versus Airflow Requirement of PCIe Card Slot (34.8 mm x 106.65 mm) at 1200m above
Sea Level for 70°C Rated QSFP |
| Inlet Temperature to the Card (°C) |
Linear Feet per Minute (LFM) |
Cubic Feet per Minute (CFM) |
Pressure (inwg) |
| 5 |
320 |
12.8 |
0.17 |
| 10 |
340 |
13.6 |
0.18 |
| 15 |
380 |
15.2 |
0.22 |
| 20 |
420 |
16.8 |
0.26 |
| 25 |
480 |
19.2 |
0.33 |
| 30 |
540 |
21.5 |
0.40 |
| 35 |
620 |
24.7 |
0.51 |
| 40 |
710 |
28.3 |
0.65 |
| 45 |
810 |
32.3 |
0.82 |
| 50 (not supported) |
930 |
37.1 |
1.05 |
Table 4. Required Flow at 1200m above Sea Level for an Example 180W
Load for 85°C Rated QSFP
| Inlet Temperature
versus Airflow Requirement of PCIe Card Slot (34.8 mm x 106.65 mm) at 1200m above
Sea Level for 85°C Rated QSFP |
| Inlet Temperature to the Card (°C) |
Linear Feet per Minute (LFM) |
Cubic Feet per Minute (CFM) |
Pressure (inwg) |
| 5 |
240 |
9.6 |
0.11 |
| 10 |
250 |
10.0 |
0.11 |
| 15 |
270 |
10.8 |
0.13 |
| 20 |
300 |
12.0 |
0.15 |
| 25 |
330 |
13.2 |
0.17 |
| 30 |
370 |
14.8 |
0.21 |
| 35 |
420 |
16.8 |
0.26 |
| 40 |
480 |
19.2 |
0.33 |
| 45 |
560 |
22.3 |
0.43 |
| 50 (not supported) |
650 |
25.9 |
0.55 |