Athlon 3700 Vs FX-55

[mpasternak]

So, i just bought the 3700 and looking at prices.

whats the fundamental differences between the 3700+ (San Diego) and the FX55. they both feature the exact same cores and sets. the only difference i can see is the higher clock spedd of the FX55. 2.6ghz v 2.2ghz.

and if thats the case, how do they warrant the difference in price? I baught it for 330 canadian while the FX55 is retailing for 1000 canadian

<P ID="edit"><FONT SIZE=-1><EM>Edited by mpasternak on 08/16/05 02:14 PM.</EM></FONT></P>

 

[RichPLS]

The LOL Athong FX is multiplier unlocked.

<pre><font color=red>°¤o,¸¸¸,o¤°`°¤o \\// o¤°`°¤o,¸¸¸,o¤°
And the sign says "You got to have a membership card to get inside" Huh
So I got me a pen and paper And I made up my own little sign</pre><p></font color=red>

 

[fishmahn]

There are 2 differences: 1) Clock speed as you've noted; and 2) FX-55 is multiplier unlocked both up and down, the 3700+ is only unlocked down.

If people will pay more for faster clock or unlocked multipliers, then that's what they do...

Mike.

<font color=blue>Outside of a dog, a book is man's best friend. Inside the dog its too dark to read.
-- Groucho Marx</font color=blue>

 

[mpasternak]

ok. so the technology IS the same. and you'd get the same performance out of the 3700 if you upped the speed to that of the FX-55?

and what is this unlocked multipleir thingy

I'm new to the idea of Overclocking.. never done it since i've always owned intell and didnt trust the heat

 

[emogoch]

There are two components that affect your "total" clockspeed: The Front Side Bus speed (FSB), and the core clock multiplier. The FSB is the speed at which the rest of your computer operates, and the Processor then runs at a multiple of what the FSB is. Thus, if you have a FSB of 200 MHz, and a processor with multiplier of 12, then you have a 2.4GHz processor.

 

[fishmahn]

Yep, the 3700+ and the FX-55 are the same CPU. They may have even been neighbors on the silicon wafer during production.

The 3700+ may outperform the FX-55 once its sped up to 2.6ghz because to get the 3700+ to hit 2.6ghz you have to run the fsb* at 236mhz instead of 200 because the multiplier can't be increased. (see multiplier explanation below)

CPUs run at a clock speed (say, 2.2ghz). The fsb runs at a different clock speed (usually 200mhz today) The multiplier is used to convert the 200mhz fsb speed to the 2200mhz CPU clock (11 in this case, so 200mhz x 11 = 2.2ghz).

Take a look at the overclocking guides in the Overclocking/CPU section. The beginner's guide to OCing the Athlon is a good source for the basics. The A64 guide deals with a few A64-specific things.

Mike.

* note: Athlon 64's (and FX's) use Hypertransport for their 'fsb', but there's still a clock setting that serves the same purpose, so for these purposes, its still commonly called an fsb (front-side bus). The Athlon XP and Pentiums use a real fsb.

<font color=blue>Outside of a dog, a book is man's best friend. Inside the dog its too dark to read.
-- Groucho Marx</font color=blue>

 

[endyen]

Not really. The FX chips are binned for certain qualities. They are made from the best parts of the die.
They are more likely to OC a little better, are capable of running at lower voltages (run cooler) and having the multiplier unlocked upwards, are a lot easier to dial in for different uses. This has become a real plus, when coupled with software managment progs like Abit's U-guru.
The FX will give a bit more, but it is a whole lot more money. I'm still too much of a cheap ass to get one.