And you'd thought those old full-height hard drives were obsolete:
So, I get in the parts to build my first dual-CPU athlon system:
Tyan Thunder K7 s2462ung mainboard (w/ dual uw160 SCSI),
two Athlon MP 1200, each with dual-fan CPU coolers,
four 256 Meg registered PC2100 DDR DIMMs (the Thunder K7 only
works with registered DDR memory), a couple of 7200RPM ATA100 drives,
Inno3d dual-monitor 64Meg GeForce2 MX400 graphics adapter,
Pioneer 16x DVD, Yamaha 2100s CDRW, and the official
Tyan-approved NMB power supply (the Thunder K7 has a "new and improved"
power connector design incompatible with both standard ATX and
P4-style connectors).
Whew!
Toss everything together in one of the Yeong Yang 15-bay cube server cases, plug in the power, and ...
... nothing ....
Tear everything down, check all the cards and cables, swap anything swappable
and reseat everything else; reapply power and ...
... nothing ....
After exploring the depths of Tyan's "technical issues" page,
- #6: Why doesn't my system power on when I press the power button?
Prior to first power up, please install system peripherals using the peripheral power
cables from the PSU, and system fans using the following fan connectors on the
m/b - Fan1, J54, J90, J58, or J56. This will ensure that the minimum load of the power
supply is met, and will assure successful system initialization during first power up.
Apparently if the power
supply thinks that there is not enough current being drawn when it fires up, it'll shut
down again immediately. Presumably the designers felt that it was extremely important
to include "underload protection" in the power supply design spec, almost important
enough to have mentioned it somewhere in the manual.
I suppose I could try calling
up some of the people on the design team and asking them what their rationale was.
Most of the time, that's more difficult, but one of the entertaining features of the bios
installed on the motherboard is
its collection of little notes burned into the firmware, reminding members of the design
team to fix this or that problem before putting the board into production.
like the story of Swamp Castle in
Monty Python and the Holy Grail,
except it whirrs a lot more |
When I've worked on product development, I've generally followed the "remove personal
notes to fix this-or-that part of the code before releasing it" philosophy, but
Tyan may feel that leaving them in is just a way to make the purchaser or system integrator
feel more involved in the product and more personally connected to the design team.
What's scary part is that all the hardware described above wasn't
enough load on the power supply for it to start up.
(Yes, there was a reason I listed all those parts up there.)
Bear in mind that each of the Athlon 1200MP processors has an average
power consumption of fifty watts. There's a reason I decided to go for the
dual-fan CPU coolers: with each half-inch chip of silicon emitting the power
of a smallish table lamp, we're approaching the territory where an uncooled
board could be in danger of finding itself populated with
a pair of light-emitting transistor arrays.
But, fortunately, I just happened to have a moderate-sized collection of older hardware
lying around, including a pile of full-height Seagate Elite-9 hard drives,
and I sat one on the desk next to the case and ran one of the four-pin power
connectors to it. That didn't make the system come up, but with one drive so attached,
it would run for half a second before shutting down.
Heartened, at least a bit, by the fans actually completing a full rotation instead of
merely twitching, I added a second full-height Seagate drive.
Then the system powered up and stayed up.
Much like the story of Swamp Castle in
Monty Python and the Holy Grail,
except it whirrs a lot more. At least it's working--and coming up with a
new use for a couple of old full-height hard drives should surely count for
something--but sooner or later I'm going to be tired of needing to have a couple
of noisy hard drives running on the desk just to be able to get the power supply
to turn on.
On the other hand, if the NMB supply will be satisfied with the extra loading put only
on the 12volt line, I might be able to get away with mounting a couple of KC lights on
top of the case, or maybe installing a headlight in a couple of the exposed drive bays.
As long as I remember to switch it to "high beams" before hitting the "on" switch,
I bet it'll work....