Affordable Dual Core from AMD: Athlon 64 X2 3800+
by Anand Lal Shimpi on August 1, 2005 9:36 AM EST- 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.
The original Athlon 64 X2 (Toledo core) processors all had the same exact specifications:
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.
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.
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 transistorsFor 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.
- 199 mm2 die size
- 110W max power
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.
Facebook
Twitter
RSS
109 Comments
View All Comments
masher - Wednesday, August 3, 2005 - link
> " believe he meant to post this review showing the X2 3800 matching or besting the XE840 in all but a handful of tests:"Let's see...the 840 wins 3DMark, half the Cinebench, Lame Encoding, DivX encoding, MPA encoding, SiSoft FP, Sisoft Multimedia, and Sphinx.
The 3800 wins the 3D shooters, PoVRay, ScienceMark, picColor, and half the Cinebench.
The Intel results are "all but a handful"?
PrinceGaz - Monday, August 1, 2005 - link
I was surprised that no attempt was made (or posted in the review) to overclock the X2 3800+, given that most people reading it here would want to know what headroom it had.Fortunately most other good sites did overclock it and post their results, and the general consensus is 2.4-2.5GHz was as much as they could do with air-cooling at reasonable voltages. Looks like the X2 3800+ really is all the speed-binned rejects, at least from the samples AMD sent out to review sites.
Houdani - Monday, August 1, 2005 - link
Well, Anand did to a tiny bit of overclocking, he just didn't do any benches with the overclock. The above snip was taken from the final page of the article.
[L]http://www.anandtech.com/cpuchipsets/showdoc.aspx?...[/L]
PrinceGaz - Monday, August 1, 2005 - link
Apologies to Anand, I was skimming through the article rather than reading it in full, and missed that. Seems like 2.4-2.5GHz is all the current batch of X2 3800+ can do, which is less than impressive. Ordered a X2 4400+ today as a result.Hacp - Monday, August 1, 2005 - link
They had a DDR2 533 1gb kit for 80 bucks at monarch I think. But I think the DDR2 667FSB chips are more expensive...Joepublic2 - Monday, August 1, 2005 - link
"Except that by the time you get a new motherboard that supports that cheaper Intel chip and the pricier DDR2 memory, any price advantage Intel had is already gone. And the AMD system still outperforms the Intel one 15% in for the 830D and 20% in the 820D. So choose wisely...""From what I can see, Intel 955 chipset motherboards are around $180 - $220, which is a lot more expensive than a decent Socket 939 motherboard. SO overall thge system cost is much cheaper than the Intel 830, and very close to the 820."
You guys obviously haven't checked prices lately. At newegg, you can get a nice ASUS 945 board for $130, which while being more expensive than an EPOX 939 at $85, is much lower than "$180-220". Also, 2GB of DDR is $177.98, and 2GB of DDR2 is $186.00. But I agree, it's worth the extra $50 over the Pentium D 820 platform.
krisia - Monday, August 1, 2005 - link
Hmmm, zipzoomfly has a 945 mobo for $110 and 1GB DDR2 ram for $92.Looks reasonable to me...
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?Pr...">http://www.zipzoomfly.com/jsp/ProductDetail.jsp?Pr...
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?Pr...">http://www.zipzoomfly.com/jsp/ProductDetail.jsp?Pr...
Hacp - Monday, August 1, 2005 - link
IMO Anand's article was the fairest. He compared the Intel 830 to the AMD 3800. Some sites compared the 820 to the 3800+ and it obviously was not fair to Intel to do that.Also, if you want an entry level processor and want multitasking, you should go with an HT enabled Intel. At 240 dollars, you should be able to buy a 3.2 GHZ Intel processor with HT enabled, which will perform WAY better at single threaded tasks and perform well in some multithreaded applications. Thats what ENTRY is. You sacrafice future performance for performance right now.
Finally, Anand, I would have liked to see the 3800+ compared to the 3.2 GHZ Intel Dual core processors. Why? Because AMD's PR numbers for single threaded applications indicate that the 3800+(2.0 GHZ with 512 Cache AKA the 3200+) should be comparable with the 3.2 GHZ processor. You shouldn't soely compare the processors on price, but also the PR system :). A 3.0 and 3.2 Intel Dual core comparision with the 3800+ X2 would have been a nice......
cryptonomicon - Monday, August 1, 2005 - link
that chip looks awesome! how come they don't have that benchmark called um,Comparison over number of Threads
or something, where they run some sort of bench over 2, 3, 4, 5, 6, threads. I always thought that was an interesting one to see how effective each processor handled multiple threads.
Samus - Monday, August 1, 2005 - link
There is no reason at this point to go with an Intel based system for general productivity (business, graphics, compression, a/v editing, 3D modeling, CAD) AND gaming (where AMD had always excelled)I couldn't agree with Anand more. Where you loose single threaded/task performance (from clockspeed) you more than make up for it in multi threaded/task performance. The overclocking potential is also fairly good, 2.46GHz is nothing to sneeze at when your talking about a 2.0GHz budget chip for 350 bucks.
Also, comparing 512KB dual cores to 1MB dual core's at the same clock speed, there is little performance difference because since the cores communicate directly via L2, not via HT (or bus like Intel) your theoretical performance-based L2 is 1MB and 2MB respectively. AMD's memory controller is so efficient to begin with that the difference between 1MB and 2MB L2 cache is very little.
The cache's are also independent (like they always have been, ie L1 and L2 being non-consecutive) so they don't hold the same information.
Boy, they've come a long way.