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Nowadays, we have ultra-fast x86 CPUs, but chipsets that hold them back. I used to have a 486 motherboard that did memory interleaving to speed up memory accesses. I suppose when we had 70ns SIMMS it was more important, as well as cheaper to implement extra memory busses due to the lower pin count on a SIMM compared to a DIMM.

Anyway, it would make sense for the current x86 chipsets to have interleaving, although with SDRAM burst reads, it might be difficult to get the timing right. Maybe that's what has prevented it in commodity chipsets? Otherwise, I suppose you could have 4 byte interleaving thus:

DIMM0:hell
DIMM1:o wo
DIMM2:rld!
DIMM3:!!!!

You would still need some really low-latency memory in-between the main memory and the processor, and I guess the cost is another barrier to use in commodity chipsets.

It's interesting to note that the Alpha architecture has up to 8 times the memory bandwidth at 5.2GB/s than Athlon at 600MB/s or 12 times the Pentium at 400MB/s (although, an Alpha machine of such can cost $13,000) - check out http://www.microway.com/products /ws/alpha_21264.html for more in-depth information.

Enjoy,
J

After I went to Ground Zero -- Compaq -- I came away with a discreet impression that they really don't want to talk to a mere peon like me. Their web site, apparently, is really put together more like a business-to-business (or government) type of a deal.

You're defintly right about that... my experience trying to spec a nice Alpha box at Compaq's site was about the same as yours. However Microway seems quite willing to sell single machines to private customers. They have a 533 Mhz 21164 (with a reasonably good setup) for $2000. For some reason the price for a NT box and a Linux box is the same, though - I guess the best move would be to order the NT machine and then install Linux (keep the NT CDs for posterity or something).

Keep in mind that some computations (e.g., solving systems of large matrices) are inherently single-threaded (since the results of one computation provide the inputs for the next). In this case, SMP will not help.

Check out the new toys at Microway -- 750MHz 21264s, 48-node Beowolf clusters, woo hoo!

What about Microway's Alpha-based systems? $1995 for a 533MHz 21164...

21164 based systems have been discontiued for some time now, see API's web site. Note the "LX" is marked as "discontinued."

Alphas are not "PC" quality or speed! There are only two (new) Alphas that I can think of that are less then $5,000 USD

What about Microway's Alpha-based systems? $1995 for a 533MHz 21164...

Your Working Boy,

Microway sells a low end Alpha workstation. Take a look at http://www.microway.com/specials/alpha.html#specia l4.

Unfortunately, Alphas have a reputation of being refridgerator-sized machines with

• AlphaLinux.Org
  A good starting place. They have tons of links to vendors, list-archives, news, FAQ's, etc.
• DCG Inc.
  I've had good luck/great service from these guys. Alpha pricing starts at $1295 for a 533-mhz bare-bones kit.
• Compaq's DS10 (21264-500mhz)
  The 466mhz model does over twice as well as a G4 in SPECfp. I seem to remember stumbling across a sale (from Compaq) for these little monsters for $2999, though I can't find the link now.
• Microway
  Never dealt with them personally, but they have fast machines and a all-around good reputation. They also sell quadputers and compilers
• eBay
  You can often find cheap Alpha hardware on eBay. Over 6 months ago, I put together a PC164-500/64mb system for about $600. Read the AlphaLinux.Org FAQ's, HOWTO's and HCL before you buy anything.

For reference, here are a few (single-cpu) spec*95 figures... (mostly from spec.org)
INT- FP-- processor
20.3 13.3 Mac G3/466mhz
22.3 15.1 Intel P-III/550mhz
21.4 20.4 G4-450 Mhz 7400
16.2 23.9 UltraSparc/450mhz
18.0 27.0 Alpha 21164/600mhz (very old now)
24.6 47.9 Alpha 21264/466mhz (new "low-end")
32.1 53.7 Alpha UP2000/667mhz

Doesn't seem very convincing to me. If people are still trying to solve QOS issues with overkill capacity then that's seems like little more than a cludge.

I should be able to do video-conferencing no problem on 10Mbit/s Ethernet (the bandwidth is there), but if the image breaks down whenever there's a burst of activity from the department file server that's a pretty fragile solution.

Overkill capacity is only overkill until someone builds a faster file server, or until you are unlucky and someone accesses a large cached file from a fast Linux machine, saturating your 'overkill' net.

Sounds to me like the difference between a real RTOS and a timesharing system. Try asking a developer who uses QNX and a 68k for a real-time app whether they would like to switch to Windows NT and an Alpha 21264-500 with overkill processing power. All the processing power/bandwidth isn't going to help you if one app decides to monoplise it.

By the way, I know that people keep trying to build RT systems out of NT. I can't imagine why. I even worked on a project that did that, and it was painful.

Check microway site. As usually one oldest company to support linux is one of the best here. Two alfas in one box. They call it biputer.

And a very expensive one:

Check www.microway.com for an Alpha cluster priced at 2500$ per node and $4,500 for the master console. This means that for the $150000 used by IBM one could assemble a 50+ node alpha cluster instead of 17 PCs...

God, when will people ever learn that x86 just does not worth it...

Everybody, please check www.microway.com before speaking of Yummy, etc. There is no such thing as a Yummy x86 based system.

On the subject, Microway have been offering Beowulf Alpha clusters for quite a while. Actually they were even supposed to present one at the Linux expo, but it looks like nobody have noticed it. This is understandable because as you can see from the pictures their stuff does not look that shiny. But it works...

And I bet that it can blast any x86 based box out of the sky...

1. DCG Inc.
   Great service, good prices. (story follows)
   I ordered myself a UX-600mhz (intergrated scsi+ether) for x-mas (last minute). The day after confirmation, they called back with news that (due to the holiday) 2mb-UX boards would be out of stock for a time. Instead of saying "Thanks for the money, you can wait a few weeks", Steve (the owner) offered me an LX (more expensive) + SCSI controller and ate the cost difference.
   I can't make any promises that they'll do the same for you, but that experience alone impressed the hell out of me.
   Anyway, if I had $5,000 to spend on hardware now, I'd either:
   • Install PVM on 2 of their $2,200 boxes (533mhz, IDE) and spend the extra on ups+disk+ram
   • Get the $4,300 "cool box" (UX-667mhz, 4mb-cache, SCSI).
2. Microway
   No personal experience here, but they're always running specials... that and everyone's heard of them.
   If you really want to chomp on data, try one of their quadputer cards (I've always wanted to...)

This is apparently the same motherboard that Microway is selling with its 6-way crossbar between the dual processor/RAM/PCI busses. The question is, with AMD set to beat Intel in absolute performance, and with high-end Alpha motherboards taking the K7, should SGI be basing their IA32 offerings on this bus instead of the P-II bus?

1. www.cpumicromart.com
   You can pick up a udb+ram for ~$180. Any old 3.5" IDE drive will do.
   Pitfalls
   1. Finding (or making) a 2.5"(notebook)ide -> 3.5"ide cable.
   2. Older UDB firmware doesn't understand IDE properly. You may need to flash an upgrade (from gatekeeper.dec.com), if so, you will need a floppy.
   These come in two models, one w/ a 3.5" hdd mounting bracket and one w/ a pci-riser. You can still cram a 3.5" hdd into the pci-slot model, but...
   1. won't be able to use a floppy. :(
   2. the hdd will stick ~2" out the front. :(
   You can install redhat (or whatever) w/o a floppy or cdrom (not for the timid)
   1. Install the hdd in a working machine.
   2. Partition it like you would any other UDB (small (8mb or so) msdos-fs hd?1 etc).
   3. Install linload.exe, milo, kernel, rootdisk, etc. in said partition.
   4. Put the drive in your Multia.
   5. Fix your boot-settings to point at the stuff you installed.
   6. Cross your fingers and boot.
   7. Make sure the RedHat-CD is NFS-exported somewhere.
   8. When (if) the RedHat installer comes up, specify NFS for the install source.
2. www.eli.com
   ELI has a few "new in box" systems left for ~$350. All original stuff, factory 540mg scsi hdd, etc. They even test their systems, offer warranty, fast delivery...

1. www.dcginc.com
   For ~$2200 you can pick up an 533mhz-LX164a with an ide-hdd and 2mb L3 cache.
2. www.microway.com
   (fyi: I have no experience dealing with microway)
   Microway has a "special" going on 533mhz-SX164pc's for $1395. These boxes only have 1mb L2 cache, but they still spec_fp better than a PII-450.