AMD's Phenom Unveiled: A Somber Farewell to K8
by Anand Lal Shimpi on November 19, 2007 1:25 AM EST- Posted in
- CPUs
Socket-AM2+, Not So Positive?
When AMD first started talking about Phenom it boasted backwards compatibility with current Socket-AM2 motherboards, as well as a new Socket-AM2+ platform that would enable higher performance and better power management.
We are currently looking into Socket-AM2 motherboard compatibility, but not all vendors have Phenom-ready code for their motherboards as of today. While Phenom should work in virtually all Socket-AM2 motherboards, it's tough to say which will work by the time you can actually buy these things.
AMD's Spider platform, well, minus the graphics card - the 8800 GTX is still our testbed GPU of choice.
Socket-AM2+ motherboards, most of which are based on AMD's new 790FX chipset, were supposed to bring a tangible performance increase when paired with a Phenom processor. Phenom's L3 cache and North Bridge work on the same power plane, one separate from the rest of the CPU. Socket-AM2+ enables the use of two separate voltages, one for the L3 cache/NB and one for the rest of the CPU, whereas Socket-AM2 motherboards run the entire chip at the same voltage. The original plan was for Socket-AM2+ motherboards to run the L3 cache/NB at a higher frequency than the rest of the chip, unfortunately it looks like AMD wasn't able to make that happen.
Socket-AM2+ in action
Currently, the L3 cache/NB on these chips runs at a fixed frequency that's actually lower than the rest of the CPU frequency: 2.0GHz. We tested Phenoms running from 2.2GHz all the way up to 2.6GHz, and in all cases the L3 cache and North Bridge ran at 2.0GHz. We're not sure if this will ever get fixed, but it's somewhat disappointing as it was supposed to be a major reason for upgrading to Socket-AM2+ (but it's good news for current AM2 owners).
Right now it looks like the only benefit to Socket-AM2+ is support for DDR2-1066, which we've been having problems with internally already. If you've got a good Socket-AM2 motherboard, you may not need to upgrade to get the most out of Phenom.
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agello24 - Saturday, February 16, 2008 - link
im still not ready to switch to intel. ill be buying my phenom shortly.PeterCollier - Tuesday, April 28, 2020 - link
How's that TLB cold bug working out for you?Verygood - Friday, January 8, 2021 - link
I’ve been in a coma for 13 years what happenedGenoR32 - Tuesday, February 5, 2008 - link
I still believe in AMD, and i know they will release a nice product line-up in the coming months, or probably 2009... i have a Core2 PC now b/c i cant deny the fact that they are really strong CPU's... but my DDR3 upgrade will be on an AM3 system... i think they will be really competitive.Greetings
JumpingJack - Sunday, September 21, 2014 - link
Are you still waiting?TheCatOfWar - Monday, April 23, 2018 - link
Not for the last year, haThatguy97 - Thursday, May 5, 2016 - link
Can't believe socket am3 is still aroundruxandy - Tuesday, October 20, 2020 - link
Well... that took a while, but it's finally happening in 2020.eye smite - Monday, January 7, 2008 - link
I didn't comment on this review when it first came out cause I didn't want to read the whole thing. It reads more like a rant on a blog than a review, he didn't want to go to Cali, so what. In the time since this article the phenom has proved to be a good cpu, I noticed in the last week that HP and Gateway have started selling systems in Best Buy and Circuit City with phenoms. This cpu was rushed out and it will take a bit of time to mature. It's the same thing we saw with the athlon64 from 2k3, had it been as developed as it needed to be, they would not have gone from socket 753 to 939 to am2 and so on. Amd should have made the smaller leaps to a quad core athlon64 til phenom was ready, but they have bad decision makers these days it seems.JumpingJack - Sunday, September 21, 2014 - link
There was no rant in this article, there was a stern condemnation of an attempt by AMD to control the benchmarking and review process, to influence what should be independent and transparent review of a product to the marketplace.