Alpha 21264 And Athlon 850 Review

Arg! writes: "Hi. There's a comparison review of an Alpha DS10 with a 466 MHz chip running AlphaLinux up at this link on Ace's Hardware. The system is compared against an 850 MHz Athlon box (also running Linux) and there are a lot of different benchmarks also showing some memory comparisons with some other PC chips, like the Celerons, as well as some Sun Ultra benchmarks. The config tested was $5500, but a base DS10 is supposed to be around $3500 ... maybe not too bad for a nice 64-bit box. ;)"

Alpha is certainly not dead.

I disagree with some people when they say that Alpha is a dying platform. In reality, it is far from dead. Aside from the hideously expensive POWER3 CPU, the Alpha is the fastest CPU out there. With the release of the EV6.7 and EV6.8, they may again capture the fastest proc known to man crown again. A 1 GHz Alpha is not that far off, Compaq demoed air cooled 1GHz Alphas a few months ago. In fact, Alpha may be the only competition left for Merced (I refuse to use that Power Ranger-esque name Itanium!) in the mid to upper range market. There was an article a while ago (on Tom's Hardware I think) cogigating on whether or not Alpha would still be faster than Merced. They cited various points about how plain RISC may beat out VLIW if implemented properly (like in the Alpha) and how the DEC guys have quite a leg up in clock speed (at least at that time.) Judging by when Merced will be out the 1GHz + Alphas should be out, and should provide quite a strong competition since
A)Alphas could just be faster, and
B) Alphas have much more market penetration and a larger support network built up. With Intel's power, that will change, but Alpha will have quite a head start on Intel.
Then there is the fact that Alpha is aimed at a much broader spectrum, and Intel might just not be able to take the market with Itanium.

Itanium vs. Alpha

The compiler situation presented by the article hilights a key advantage that Compaq has over Itanium. The compiler needed to take advantage of Alpha is already freely available, while (if intel keeps with it's current practice of charging for it's compiler) one would have to pony up quite a bit for Intel's compiler. The compiler is critical because Itanium (based on VLIW, which places all code ordering work on the compiler) is heavily dependant on a good compiler for any semblance of performance. Sure GCC compiles Itanium code, but if it can barely optimize x86, do you really think it has any hope of producing good Itanium code? This might not be important on Windows, but as OSs like Linux and BeOS, which depend on the freely available gcc to compile many of the applications, the availibilty of a good free compiler is very important.

Multias

Of course, if you want an entry level 64 bit Alpha workstation, you can get a Multia (or UDB, as they're sometimes called) on ebay for around $75-$150 (depending on how decked-out it is).

Many cheap Multias come with a soldered 166 MHz CPU, no floppy drive, and no hard drive. The more expensive ones (~$25 extra) have a socketed 166 or 233 MHz CPU, a floppy drive, and sometimes even a small hard drive (400 or 500MB).

These Multias run Alpha Linux just fine. They're around the speed of a Pentium 100 at integer computations, and a Pentium 200 at floating point.

You also might want to look at the 21164A, which is quite cheap these days. You can get a 533 MHz CPU, motherboard, and perhaps even a DIMM for around $500. This will be about the same speed (or a little faster) than a 450 MHz Pentium III at integer ops.

Older systems are much cheaper...

I have a 21164 500Mhz box with 256MB of memory, total cost was around $1k. This was when memory was expensive, too...

Not a bad system at all. Nowhere near as fast as the 21264's, but much, much, cheaper. It would have been pretty usable with less memory, too...

What can I say?

The MHz's must be smaller on an Athlon than on an Alpha. This is similar to the US gallon vs the UK gallon problem. It's time we switch to metric units when reporting computer speeds.

Re:Motherboard Support

Every AMD 750 and Via KX133 motherboard supports the Athlon's 100 MHz DDR front side bus. DDR stands for "double data rate", which is chip-speak for "it transfers data effectively twice as fast". If you take an electrical engineering class (microprocessors, for example), you'll learn that data is transmitted on the bus only at certain times (defined by the clock).

For example, consider that the bus is on a 24 hour clock. The Pentium II with its 100 MHz bus transfers data at 12:00 noon. The Athlon, with it's 100 MHz DDR bus, transfers data at both 12:00 noon and 12:00 midnight.

I hope that explains it.

Building an Alpha

Don't let the "budget" label fool you, though, as the system still carries a hefty price tag of +/- $3500.

Cool! Where do I find the -$3500 deal? ;-)

Let me point out an article I liked from Linux Gazette [linuxgazette.com] on how to build your own inexpensive Alpha [linuxgazette.com]. It's almost 2 years old, so some of the details aren't as relevant, but I think some of the stuff explaining the gotchas of the Alpha platform for someone used to x86 (like me) are still informative.

I still want to actually build my own Alpha... as the Penguin-Ferrari article points out, we need diversity, and anyway I like messing with different stuff. Anybody know of more recent articles, or have personal experiences to offer?

Slightly misleading ...

... in the comment that HP is betting solely on EPIC and MIPS has stopped processor development altogether. Given the slippage in Intel's original roadmap for Merced, HP were smart to keep a hand in the PA-RISC and while MIPS may not be revving their processors like the others, they earn a very tidy income from licensing their IP and creating variants of their processors for the embedded market while continuing to source high-end designs from SGI (who still have a 5 year roadmap for their R14K, R16K).

From a personal perspective, it is rather disturbing from an architecture point of view that so much attention is focused on the branding and MHz rating. If we use the analogy of cars, the peak revolutions per minute has got nothing to do with the actual real-world engine performance. A lot of factors depend on the I/O subsystem (gas tank + injection system), cache design (suspension), and more recently stlying (bodywork). Just because it runs hot, doesn't mean that it runs well, in fact from a thermodynamic perspective excess heat is an indication of inefficiency. Just as in real-life, there is a distinction between buses (good ol' shared memory Suns), industrial trucks (IBM workhorses), SUVs (SGI drool-designs) or motorcycle packs (Beowulfs). Pretending a souped up scooter with over-granished rusty frame can do the job of everything is a serious indication of cluelessness or delusion.

Just as in real life, the limitation is the overall transport system (network) which is still an information back-lane despite the heavy hype. Sure a speed-demon Porsche (Alpha) can outrun anything in a speed race but most people settle for a Ford (Intel) or Chevvy (AMD) to commute to work. Some may prefer a flashier Saab (Apple) or stick with the boring but solid Volvo (IBM) or even go upmarket with a BMW (SGI) but they all serve a basic purpose (mobility) and dominate specific niches. You get paid for maintaining a professional non-bias and correctly matching your company's needs to the available choices.

The quasi-technical mainstream press really has to
get their act together if reading the IT section in any general newspaper is any indication ... more like unpaid advertising sometimes. I suspect that past 1 GHz, the CPU performance is of only marginal benefit (outside niche areas) as the speed limit is the bandwidth limitations anyway.

LL