Content deleted Content added
Reverted 1 edit by 188.253.7.166 (talk): Off topic |
rm comment explained in text further down. ce for focus. |
||
Line 17:
Some microprocessors in the 1990s, such as the DEC [[Alpha 21066]] and HP [[PA-7300LC]], had integrated memory controllers; however, rather than for performance gains, this was implemented to reduce the cost of systems by eliminating the need for an external memory controller.{{cn|reason=The linked articles do mention a cost motivator but there are no supporting citations.|date=July 2024}}
Some CPUs are designed to have their memory controllers as dedicated external components that are not part of the chipset. An example is IBM [[POWER8]], which uses external [[Centaur (computing)|Centaur]] chips that are mounted onto [[DIMM]] modules and act as memory buffers, [[L4 cache]] chips, and as the actual memory controllers. The first version of the Centaur chip used DDR3 memory but an updated version was later released which can use DDR4.<ref>{{cite web|url=https://www.itjungle.com/2016/10/17/tfh101716-story02/|title=IBM Brings DDR4 Memory To Bear On Power Systems|last=Prickett Morgan|first=Timothy|date=2016-10-17|website=IT Jungle|pages=1|access-date=2017-09-07}}</ref
== Security<span class="anchor" id="SCRAMBLING"></span> ==
A few experimental memory controllers contain a second level of address translation, in addition to the first level of address translation performed by the CPU's [[memory management unit]] to improve cache and bus performance.<ref>John Carter, Wilson Hsieh, Leigh Stoller, Mark Swansony, Lixin Zhang, et al. [http://www.cs.utah.edu/~ald/pubs/hpca99.pdf "Impulse: Building a Smarter Memory Controller"].</ref>
Memory controllers integrated into certain [[Intel Core]] processors provide '''memory scrambling''' as a feature that turns user data written to the main memory into [[pseudo-random]] patterns.
| url = http://www.intel.com/content/dam/www/public/us/en/documents/datasheets/2nd-gen-core-desktop-vol-1-datasheet.pdf
| title = 2nd Generation Intel Core Processor Family Desktop, Intel Pentium Processor Family Desktop, and Intel Celeron Processor Family Desktop
Line 32:
| date = September 2012 | access-date = 2015-11-03
| page = 24
}}</ref> Memory scrambling
| url = http://www.slideshare.net/codeblue_jp/igor-skochinsky-enpub
| title = Secret of Intel Management Engine
Line 40:
}}</ref>
ASUS and Intel have their
== Variants ==
|