VPX6600
USER
’S MANUAL
Acromag, Inc. Tel: 248-295-0310
- 19 -
http://www.acromag.com
- 19 -
https://www.acromag.com
3.2 Power Supply and Management
3.2.1 Power Supply Requirements
The VPX6600 must be supplied both +3.3V and 5V from the VPX backplane.
For allowed voltage ranges and expected power draw, see the specifications listed
in
3.2.2 Programmable CPU Power Limits
The VPX6600 features programmable power limits, allowing the user to 'dial-down'
the maximum power consumption of the CPU in systems where power is a concern.
The graph below shows that the E3-1505M CPU outperforms other available
embedded Intel CPU's at every power point from 5W - 47W.
By simply programming a lower power limit in the BIOS setup, the CPU can be used
in applications where less power is available or heat removal is an issue. This is
accomplished by the CPU automatically underclocking its frequency to maintain a
power level at the set limit.
Note:
Once the minimum frequency of 800MHz is reached the programmed limit
could be exceeded. Extremely large workloads have a realistic minimum power of
around 20W. However, light to medium workloads can effectively maintain a power
limit as low as 5-10W.
There are two programmable CPU limits. These are the long-term average Power
Limit 1 (PL1) and the short-term Power Limit 2 (PL2). Depending on a windowed
Power Limit 1 Time 'constant', the CPU can spend a short time above power level
PL1 up to a maximum of PL2, allowing a significant performance boost for short
workloads. If the CPU power remains above PL1 at the end of this time the power is
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CPU
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Power Rating or Throttle Setting (W)
E3-1505M (5-45W)
i7-4700EQ (5-47W)
i7-3612QE (35W)
i7-3615E (45W)
i7-3517UE (17W)
Atom E3845 (10W)
