Subject: Re: what's this machine check mean?
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Wilko Bulte <wkb@chello.nl>
List: port-alpha
Date: 04/15/2000 20:12:53
On Sat, Apr 15, 2000 at 02:04:15PM -0400, der Mouse wrote:

> What I got is motherboard-plus-CPU.  I added RAM, laid it flat on a
> nonconducting surface (melamine-coated chipboard); connected power
> supply, serial (after discovering a lovely pinout gotcha), and SCSI;
> added a PCI Ethernet I've been hanging onto against the day I get a
> PCI-capable machine; set up fans to cool the processor and the 3.3V
> regulator next to it; and away I went.
> 
> The machine seems to be accurately described in the
> 
> 	Digital AXPpci33
> 	Alpha PC Motherboard
> 	OEM Design Guide

This is known as a "NoName" (confusing name..) 

> I now suspect memory.  A fuzzy memory of reading the aforementioned PDF
> file prompted me to check the memory.  The docs say it needs 70ns
> memory, and my 72-pin memory seems to all be rated at 80ns.  I do have
> 4MB of 30-pin 70ns memory, and some 4x30pin->72pin adapters, but even

Yikes..

> if that works, I don't have enough 30-pin 70ns memory to fill up two
> 72-pin slots...and this board takes its memory in pairs.  I'm going to
> be searching for 70ns memory, and won't worry about the machine checks
> unless they keep happening even with 70ns-rated parts.

These 30->72 pin converters will most likely overload (much more chips!)
the memory bus of the machine. Be careful, you can screw the CPU this way,
I once had a friend with a fried CPU, a lot of logic directly connects to
the CPU without buffer chips in between.

It takes memory in pairs of 2 alright.

I have the latest copy of the NoName OEM guide at
ftp://www.tcja.nl/pub/wilko if you need it.

-- 
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