[rescue] Re: Re: AXi vs. Ultra 30

[Robert Novak]

On Tue, 7 May 2002, James Lockwood wrote:

> On Tue, 7 May 2002, Robert Novak wrote:
> 
> > AXi will take faster CPUs (up to 440MHz) but only up to 1GB RAM. Uses RAM
> > similar to U5/U10 in banks of two. Fun with column addressing modes.
> >
> > Ultra 30 will take up to 300MHz CPU but up to 2GB RAM, and two UPA
> 
> 400MHz/2MB modules work, though Sun doesn't officially support them.  SME
> has 480MHz/2MB IIi modules for the 5/10/AXi though remarkably few have
> escaped into the wild.

Ah, okay. I'd asked about the 400mhz modules here a few weeks ago (when I
got my first U30) and didn't hear any good news. They're still not cheap,
so it's a non-issue for me today. 

> > vertical framebuffers (ignore this part though). Uses Ultra 1/2 style RAM
> > in banks of 4. If it works in a U1 or U2, it works in a U30.
> 
> Pairs of 2.  With banks of 4 you get interleave and increased performance,
> but there is no requirement to interleave.  16 DIMM slots in the U30 so
> you can get to 1GB using cheap 64MB SS20 DIMMs.

Ah, this is good to know. I've assumed banks of 4. Sun System Handbook
doesn't hint at the pairs option ("16 DIMM module slots, Install SIMMs in
sets of four. 16-, 32-, 64-, and 128-MB DIMM expansion 2 GB total memory
capacity"). I haven't tried it myself yet... maybe I should before I tear
my U30 apart. I did notice the diags show 8 banks, although at the e nd
where it inventories slots and stuff, it shows 4 banks.

> AXi has dual onboard UW SCSI.  U30 has a single channel (U60 added a
> second channel).  U30 has neato spiffy 2-slot SCSI backplane using SPUD
> brackets, AXi has whatever the chassis it is in has.

Yep. U30 will take half-height drives too, and 36gb/50gb disks are cheaper
in HH than in LP. I just sold a 2x36GB U30 today... pretty cost-effective
for a home Oracle system or the like. 

> Creator/Elite on AXi blocks a PCI slot (not a concern for you).

I haven't tried it yet, but can you do two Elite3d-m3 cards in a U30?
There's some heatsinkery that makes it look like a tight fit at best.

> U30 can support a software-eject floppy drive (now THERE's a big
> feature for you).  :)

Oooh. My last batch had manual eject, but I don't often use a floppy on a
Sun anyway.

> Here's my opinion: the original poster said that case was in favor of
> the AXi.  I would go for the U30 unless the case and cabling of the
> AXi was absolutely immaculate, and ventilation was plentiful.  The AXi
> is a terrific board but I have seen far too many of them stuffed into
> poor quality chassis that induce overheating problems and make
> maintenance a nightmare.

I'd have to agree. The two I've seen were pretty good... one rackmount
from Marner, and one desktop that was customized by its original owner. 

--Rob

Robert Novak, Indyramp Consulting * rnovak at indyramp.com * indyramp.com/~rnovak
	"I don't want to doubt you, Know everything about you
      I don't want to sit Across the table from you Wishing I could run."