X-bit labs

Core Micro-Architecture Comes to Celeron Processors: Conroe-L Preview (page 2)

Category: CPU

by Ilya Gavrichenkov

[ 04/03/2007 | 05:53 PM ]

Celeron 4XX: First Look

Celeron processors based on Core micro-architecture are scheduled to be officially launched in June. According to the available info, the new Celeron family will first contain only three models marked as 4400, 430 and 420. These processors will be priced very attractively: between $40 and $60. So, Core micro-architecture should get into the budget systems very quickly. Celeron 4XX processors will be based on another modification of Conroe core aka Conroe-L. The main distinguishing features of Conroe-L are single-core design, cut-down 512KB L2 cache and 800MHz Quad Pumped Bus. The first Celeron 4XX processors will run at relatively modest clock speeds ranging from 1.6GHz to 2.0GHz.

The Celeron 4XX engineering sample based on Conroe-L we got at our disposal didn’t have any marking on it and featured an unlocked clock frequency multiplier. We could notice the difference between this CPU and the solutions built on Conroe and Allendale cores with the naked eye. You can easily distinguish this processor from the others by the typical placement of electronic components on the bottom side of it.

We had some issues with the installation of the CPU into our test platform based on ASUS P5B Premium mainboard with BIOS version 402. This BIOS version wasn’t familiar with Conroe-L, so on system boot-up the CPU was recognized as Genuine Intel CPU, and after the POST stage the mainboard reported: «Intel CPU uCode Loading Error. Press F1 to Resume». However, after pressing F1 key the system would boot-up successfully and the system would operate flawlessly after that.

Unlike the BIOS, CPU-Z utility version 1.39 handled the situation better and reported absolutely correct info about our processor sample:

The utility recognized our processor as Celeron with Conroe-L codename. As you can see from the screenshot, our sample allows setting the clock multiplier at up to 12x, which allows us to have this CPU work at up to 2.4GHz frequency taking into account 800MHz bus. Looks like this sample has some hidden reserve for the “future needs”, because the maximum frequency of mass Conroe-L coming out in June will be only 2.0GHz.

The CPU supports 64-bit EM64T extensions present in all contemporary processors. However, some functions typical of the Conroe core will be disabled Celeron family, as usual. Budget CPUs will lose Virtualization Technology and most likely Enhanced Intel SpeedStep support.

So, if we compare the specifications of contemporary Celeron processors on NetBurst micro-architecture with those of the upcoming Celerons on Conroe-L, we will get the following picture:

In other words, Conroe-L processors do not have anything impressive to boast. Of course, new micro-architecture and 800MHz bus are good things, but don’t you think that the clock frequencies Intel set for their budget single-core processors are somewhat too low? However, even during the comparison with “fully-fledged” dual-core processors we concluded that CPUs on NetBurst micro-architecture will have to run at 90-100% higher clock frequency in order to catch up with their counterparts on Core micro-architecture. If this rule also works for the budget Intel processors, then the new Celeron CPUs on Conroe-L core will turn out much faster than their predecessors based on Cedar Mill.