Affordable Dual Core from AMD: Athlon 64 X2 3800+ ( 2005 Anandtech Review )

Anandtech ^ | 8/1/2005 9:36:40 AM | Anand Lal Shimpi

[Ernest_at_the_Beach]

Posted in CPUs

For the past couple of months, we've asked, hoped and dreamed for it, and today, AMD is launching it - the $354 Athlon 64 X2 3800+; the first somewhat affordable dual core CPU from AMD.

If necessity is the mother of invention, then the birth of the Athlon 64 X2 3800+ should be no surprise to anyone. In one of their strongest CPU paper-launches ever, AMD put their best foot forward this past May and introduced the Athlon 64 X2 processor. While AMD was late to the desktop dual core game compared to Intel, the Athlon 64 X2 processor had absolutely no problem outperforming Intel's Pentium D. But at the end of the day, despite AMD's clear victory, our recommendations were quite complicated, thanks to one major flaw in AMD's execution: price.

The cheapest dual core Pentium D processor could be had for under $300, yet AMD's cheapest started at $537. Intel was effectively moving the market to dual core, while AMD was only catering to the wealthiest budgets.

The Pentium D 820, running at 2.8GHz and priced at $280, offered the most impressive value that we've seen in a processor in quite some time - if you could properly use the power. Multitaskers and users of multithreaded applications found themselves with the cheapest 2-way workstation processor that they had seen since the SMP Celerons and ABIT's BP6. While Intel satiated our demands for affordable dual core, we knew it wasn't the perfect option. AMD's Athlon 64 X2 was the better overall performer, just at the very wrong price point.

After much pressure from all sides and some very important manufacturing changes, AMD went ahead with the decision to release a cheaper Athlon 64 X2. The decision was made around the time of Computex 2005 and that's when we first heard of the $354 Athlon 64 X2 3800+.

The Athlon 64 X2 3800+ is basically two Athlon 64 3200+ cores stuck together, each running at 2.0GHz and each with its own 512KB L2 cache. This is a full 200MHz lower clock per core than the 4200+, but with the same amount of cache.

Note: The 512KB X2s are available in both 154M and 233M transistor versions. Looking at the table above, it is clear that AMD has left room for another SKU - potentially an Athlon 64 X2 4000+ at 2.0GHz, but with a 1MB L2 cache. AMD could also go lower, pairing up a couple of 1.8GHz/512KB cores, but AMD most likely wanted to find a good balance between single threaded performance, price and multithreaded performance with this new "entry level" X2 core.

A New Core

AMD didn't sit on the X2 3800+ just because they were greedy and expected everyone to gobble up the $500+ parts. Instead, today's release is the result of a slightly revised core, codenamed Manchester, specifically designed to cut costs.

The original Athlon 64 X2 (Toledo core) processors all had the same exact specifications:

- 233.2M transistors
- 199 mm² die size
- 110W max power

For the Athlon 64 X2 4800+ and the 4400+, the shared transistor count and die size made sense. They both were identical from a transistor standpoint, one chip just ran 200MHz faster than the other. But the 4200+ and the 4600+ weren't identical; unlike the 4800/4400+ X2s, the 4200+ and 4600+ only had a 512KB L2 cache per core, not a 1MB L2.

Update: As many of you have correctly pointed out, the 4200+ and 4600+ were available as both Toledo and Manchester cores. More than half of the Athlon 64 X2's transistor count is spent on cache, which means that if there are going to be any manufacturing defects on the chip, they will more than likely occur in the processor's cache. Born out of that fact, the Toledo based Athlon 64 X2 4600+ and 4200+ were nothing more than 4800/4400+ X2s with too many manufacturing defects; instead of throwing the bad cores away, AMD simply rebranded them and sold them at lower price points. The problem with this approach is that an Athlon 64 X2 4200+ took the same amount of space on a wafer as an Athlon 64 X2 4800+, despite only having half the cache. Thus we have the Manchester core: a core designed from the ground up to only feature a 512KB L2 cache per core.

As manufacturing ramps up, yields improve and it is now possible to actually create a cost-reduced Athlon 64 X2, using the smaller Manchester die - and that's where the Athlon 64 X2 3800+ gets its cost savings.

The transistor count of the 3800+ goes down to 154 million, and the die gets shrunk down to 147 mm² compared to the 233.2M and 199 mm^2 of its bigger brothers (4800/4400+). The thermal envelope of the new core also dropped from 110W down to 89W, both still lower than Intel's Pentium D or single-core Pentium 4 for that matter.

With a smaller die and lower transistor count, the Athlon 64 X2 3800+ is able to support its $354 price tag.

************************************SNIP********************************************

[Ernest_at_the_Beach]

Came across this in the comments to an xBit article:

AMD's Initial Lineup of FX-Series "Vishera" Chips to Consist of Three Models.

********************************

[08/28/2012 09:55 PM]

[MCH]

???? What’s the reason for posting ancient technology announcements? Is it an anniversary or something, like the posts from WWII that happened on the same day?

[Moltke]

A seven year old CPU review is like a 70 year old car review. If there is any connection to the release of new AMD CPUs, what is it? What am I missing here?

[Ernest_at_the_Beach]

I like going back in the History of all of this hiTech.....

*********************************EXCERPT************************

The punch line:

*******************************************************

The victory is clear and without debate, at the $300 - $400 price point, the Athlon 64 X2 3800+ is the dual core processor to get.

[Ernest_at_the_Beach]

The point is that AMD did takeon Intels products successfully before.....

Maybe it is possible again....

The comments to the xBit article gets into whether AMD's role will be replaced by the ARM products and perhaps even MIPS!!!!

[Moltke]

OK, got it. (A humble suggestion: put that comment in the top post so folks know what the motivation for posting was!)

[Usagi_yo]

I’m confused, what do I do with my 6 core $199 2.8 Ghz AMD processor?

[smokingfrog]

[Ernest_at_the_Beach]

Keep it going....or more onto the 8 core .....

[Ernest_at_the_Beach]

OH!!!

I like that!

[libh8er]

I washed my hands off AMD last year after being a supporter for many years. I no longer support companies simply because they are underdogs and no high end CPU from AMD can touch a high end CPU from intel. So intel it is. My i7/2600k CPU is blazingly fast !

[puppypusher]

I would just like to see AMD meet or exceed Intel’s mid-level to top processor in horse power.

It’s not that I think they make bad CPU’s it’s just that it seems you have to update more often to maintain some semblance of parity.Especnially with gaming.

[Ernest_at_the_Beach]

Not enough space... I did get the date of the article into the title space.

[Ernest_at_the_Beach]

Well clearly the Gaming enthusiasts have pretty much gone over to Intel....

But when are the Game developers going to starting using more that a few cores?

[Marine_Uncle]

"The point is that AMD did takeon Intels products successfully before.....Maybe it is possible again..."
Tis a brutal business at best.

[Ernest_at_the_Beach]

TYPO correction:

to start using

[SunkenCiv]

Thanks Ernest. How’d it go, anyway? :’) AMD’s always behind Intel, that doesn’t seem to have changed in that seven year interval.

[death2tyrants]

affordable dual core CPU from AMD

"AMD didn't build that!"