I think you're very close to resolving your problems.

:-)

Processor speed -

The "Autodetect" bios settings (which I try to stick to, because I'm not interested in overclocking) gives me a choice for processor speed: 1250mHz or 1667mHz. Why is this, exactly? The 2000 + processor doesn't actually run at 2000mHz, I know that much, but I'm not sure which of those is the proper setting. I do know that currently if I set it to 1667 the computer reboots endlessly, so 1250 is the "workable" one.

Bus speed -

The bus speed defaults to 133 when the cpu is set to 1667, and 100 when set to 1250. I have no idea why, since when the Athlon 1000 was installed it was always at 133. I don't have one of those new 266 boards, and I don't have any of that super-RAM either, but I do have RAM that runs at 133. Why would the board scale back to 100, ever?

At 1000 MHz, your system is running 133 MHz x 7.5, so it's not having to be driven as hard as when it's trying to run faster. Memory timing issues between the CPU and memory aren't quite as critical in the slower case.

Your system is giving you choices of 1250 MHz (12.5 x 100 MHz) or 1667 MHz (12.5 times 133 MHz) with the 2000+ processor. For your 2000+ (1667 MHz) processor to run at 1667 MHz, it has to run at 12.5 times the 133 MHz memory clock. If it won't run there, it means that there's some memory timing issue or something similar. Sometimes these issues can be resolved by tweaking the CPU voltage, but that'll make it run hotter. I've never done such tweaking.

Since only the 12.5 x 100 MHz version is working, it seems to be saying that your memory won't run at 133 MHz (at least on this board with this CPU at the moment). You could try using SpeedFan (mentioned earlier) to slowly tweak your memory clock and see if you can squeeze a little more speed out of it. On my Abit 1000 MHz Athlon system, I have choices of 100, 101.5, 103, 105, 107.5, 110, 112, 115, 117.5, etc. Note that increasing these frequencies also increases your PCI bus speed, so it may affect the stability of your peripherals as well.

I rechecked your motherboard specs and it does use PC133 RAM rather than DDR. It does seem a little risky to me, though, to try to run such a fast processor with relatively slow memory like that, but others have reported success.

[link|http://www.active-hardware.com/english/reviews/mainboard/a7v.htm|This] review of your board talks about various jumpers and ways of tweaking things in the BIOS. You might want to glance at that, if you haven't done so.

Bottom line: I think it's the RAM or RAM settings.

Good luck!

Cheers,
Scott.

if they are. The RAM (what brand and specs, BTW?) may be fine on another machine. In [link|http://www.anandtech.com/showdoc.html?i=1303&p=3|Anandtech's review of this board] they recommend Corsair or Muskin memory. Newegg.com has a 512 MB stick of PC133 Corsair CL-2.5 memory for $67. I've been happy with my Soyo K7V Dragon+ using Crucial memory. Newegg's cheapest Soyo board is $78. 512 MB of Crucial DDR for it would be $128.

If you don't have money to burn, *don't* buy anything. Just use what you've got but tweak it until it's reliable (even if you have to run it slightly slowly). Things will always be faster and cheaper in the future. :-)

You shouldn't need more than 300 W for your system. 500 W is overkill unless you've got lots of PCI cards (e.g. SCSI cards) and lots of hard drives.

According to [link|http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/24309.pdf|this], your 2000+ dissipates a maximum power of 70 W (maximum chip temperature of 90 C). It draws a maximum of 40 A at 1.75 V (35.7 A typical). [link|http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26003.pdf|This] AMD paper gives you pointers on how to calculate how big a PS you need. 300 W should be plenty if it's an ATX12V supply.

HTH.

Cheers,
Scott.
(Who thinks his 1.2 GHz Athlon home system is plenty fast enough right now...)