Dual-core Celerons include the same power-saving features

 Intel Celeron Dual-Core processor family is the latest generation of Celeron-branded budget microprocessors. The family was introduced in January 2008, and currently consists of 7 desktop and 9 mobile microprocessors. The Celeron Dual-core family is based on Core microarchitecture, and includes all basic Core features:

• 32 KB instruction and 32 KB data cache per core;
• Level 2 cache shared between two cores.
• Support for SSE3 and Supplemental SSE3 instructions. Improvements in Core micro-architecture allow the CPU to execute up to one 128-bit SSE instruction each clock cycle.
• Intel 64 technology, formerly known as Extended Memory 64 Technology, or EM64T.
• Disable bit feature. When supported by operating system, this feature prevents system infection by certain group of viruses and malicious programs.
• Desktop Celeron E3xxx processors, based on newer Wolfdale core, feature Virtualization technology.

from:
http://www.cpu-world.com/CPUs/Celeron_Dual-Core/index.html