Kayak XU800 memory error

Hello,

I've upgraded a known-to-work XU800 (i840 chipset) with HP11.08GR BIOS
to 1GB RAM using Elpida MC-4R256FKE8D-845 PC800 ECC memory RIMMs.
There are 4 identical modules at 256megs each which are supposed to
work fine as well. HP p/n is 1818-8540. (This doesn't match HP p/n for
XU800 accessories, though, but they should work in any PC800 eating
RDRAM monster).

The machine shows "memory error" on the MaxiLife display. It also does
this if I put in 2 of the 128meg modules. The memory error just goes
away if I plug back in all 4 128meg modules.

Is there a specific way to upgrade memory or are the modules
incompatible due to their specification? TIA

What are the manufacturer and the part number on the 128MB RDRAM modules?

All I can find out about the XU800 is that it requires PC800 ECC memory. PC800
was manufactured in two speeds: PC800-45 and PC800-40. I have no idea why a
Pentium 3 system would require the faster PC800-40, but HP has done some very
odd things with its more proprietary Penium computers. And RAMBUS is pretty
odd, too.

All P4 and many P3 RAMBUS motherboards (I840 chipset, I suppose) require memory
to be installed in matched pairs. I am assuming that you know that if you
install only one matched pair of memory, then the vacant memory slots need to be
occupied by continuity RIMMs (CRIMMs)? ... Ben Myers

On Thu, 31 Jan 2008 00:39:23 -0800 (PST), "Christian Dürrhauer"
<> wrote:

>Hello,
>
>I've upgraded a known-to-work XU800 (i840 chipset) with HP11.08GR BIOS
>to 1GB RAM using Elpida MC-4R256FKE8D-845 PC800 ECC memory RIMMs.
>There are 4 identical modules at 256megs each which are supposed to
>work fine as well. HP p/n is 1818-8540. (This doesn't match HP p/n for
>XU800 accessories, though, but they should work in any PC800 eating
>RDRAM monster).
>
>The machine shows "memory error" on the MaxiLife display. It also does
>this if I put in 2 of the 128meg modules. The memory error just goes
>away if I plug back in all 4 128meg modules.
>
>Is there a specific way to upgrade memory or are the modules
>incompatible due to their specification? TIA

Christian D?rrhauer <> wrote:
> Hello,
>
> I've upgraded a known-to-work XU800 (i840 chipset) with HP11.08GR BIOS
> to 1GB RAM using Elpida MC-4R256FKE8D-845 PC800 ECC memory RIMMs.
> There are 4 identical modules at 256megs each which are supposed to
> work fine as well. HP p/n is 1818-8540. (This doesn't match HP p/n for
> XU800 accessories, though, but they should work in any PC800 eating
> RDRAM monster).
>
> The machine shows "memory error" on the MaxiLife display. It also does
> this if I put in 2 of the 128meg modules. The memory error just goes
> away if I plug back in all 4 128meg modules.
>
> Is there a specific way to upgrade memory or are the modules
> incompatible due to their specification? TIA

I have an x4000 and had problems with RIMMs that were eith single or dual
channel (if that's the correct term, and I have no idea what it means with
RIMMS). The visible difference was some modules had chips on two sides of
the board and two heatsinks, and one set was with one row of chips and a
heatsink. All memory was HP part numbered.

Moving around the original 256MB modules around and putting the two new
256MB modules in the original slots worked.

Never toss out your the dummy RIMM cards- you'll need them for testing or
using the system if you ever go back to two RIMM modules.

I don't know what the exact RAMBUS term is either, but a RIMM of a given
capacity can have either of two numbers of chips on it. For example, there are
256/16 and 256/8, and 128/8 and 128/4. Some RAMBUS motherboards absolutely
require ECC, and some can run with either ECC or non-ECC, with ECC checking
disabled. The Kayak XU800 apparently requires PC800 ECC, so the OP has that
part absolutely correct. The remaining open question is whether the faster
PC800-40 is required, not PC800-45. I suspect that it is... Ben Myers

On Thu, 31 Jan 2008 18:35:15 +0000 (UTC), Cydrome Leader
<> wrote:

>Christian D?rrhauer <> wrote:
>> Hello,
>>
>> I've upgraded a known-to-work XU800 (i840 chipset) with HP11.08GR BIOS
>> to 1GB RAM using Elpida MC-4R256FKE8D-845 PC800 ECC memory RIMMs.
>> There are 4 identical modules at 256megs each which are supposed to
>> work fine as well. HP p/n is 1818-8540. (This doesn't match HP p/n for
>> XU800 accessories, though, but they should work in any PC800 eating
>> RDRAM monster).
>>
>> The machine shows "memory error" on the MaxiLife display. It also does
>> this if I put in 2 of the 128meg modules. The memory error just goes
>> away if I plug back in all 4 128meg modules.
>>
>> Is there a specific way to upgrade memory or are the modules
>> incompatible due to their specification? TIA
>
>I have an x4000 and had problems with RIMMs that were eith single or dual
>channel (if that's the correct term, and I have no idea what it means with
>RIMMS). The visible difference was some modules had chips on two sides of
>the board and two heatsinks, and one set was with one row of chips and a
>heatsink. All memory was HP part numbered.
>
>Moving around the original 256MB modules around and putting the two new
>256MB modules in the original slots worked.
>
>Never toss out your the dummy RIMM cards- you'll need them for testing or
>using the system if you ever go back to two RIMM modules.

Ben Myers <> wrote:
> I don't know what the exact RAMBUS term is either, but a RIMM of a given
> capacity can have either of two numbers of chips on it. For example, there are
> 256/16 and 256/8, and 128/8 and 128/4. Some RAMBUS motherboards absolutely

Hmm, that /8 /16 part sounds familiar. Even when RIMMs were a big deal,
nobody seemed to know what it really meant.

The BIOS setup menus in a Dell RAMBUS system show the exact characteristics of
the RIMMs installed. If a RIMM does not have the aluminum heat sink on one side
(and, of course it does not have chips on that side), you can count the chips
from the back uncovered side... Ben Myers

On Thu, 31 Jan 2008 22:38:51 +0000 (UTC), Cydrome Leader
<> wrote:

>Ben Myers <> wrote:
>> I don't know what the exact RAMBUS term is either, but a RIMM of a given
>> capacity can have either of two numbers of chips on it. For example, there are
>> 256/16 and 256/8, and 128/8 and 128/4. Some RAMBUS motherboards absolutely
>
>Hmm, that /8 /16 part sounds familiar. Even when RIMMs were a big deal,
>nobody seemed to know what it really meant.

Christian Dürrhauer wrote:
> Hello,
>
> I've upgraded a known-to-work XU800 (i840 chipset) with HP11.08GR BIOS
> to 1GB RAM using Elpida MC-4R256FKE8D-845 PC800 ECC memory RIMMs.
> There are 4 identical modules at 256megs each which are supposed to
> work fine as well. HP p/n is 1818-8540. (This doesn't match HP p/n for
> XU800 accessories, though, but they should work in any PC800 eating
> RDRAM monster).
>
> The machine shows "memory error" on the MaxiLife display. It also does
> this if I put in 2 of the 128meg modules. The memory error just goes
> away if I plug back in all 4 128meg modules.
>
> Is there a specific way to upgrade memory or are the modules
> incompatible due to their specification? TIA

just wanted to let everyone know that I was eventually able to get the
system up and running.

What did I do? I upgraded to BIOS 11.10US with the old RAM and then read
the ****ing manual and found out something. I already knew that RIMMs
need to be installed in pairs, however, I wasn't aware of how the pair
needs to be deployed on the MEC. Once I got this right, I now have a
XU800 with two 1GHz PIIIs and 1GB PC800-45 ECC RAMBUS memory. Together
with two 15k Fujitsu harddisk drives, this should make for a reasonable
fast Win2k system.

Thanks anyway to both of you!

Christian

Christian D?rrhauer <> wrote:
> Christian D?rrhauer wrote:
>> Hello,
>>
>> I've upgraded a known-to-work XU800 (i840 chipset) with HP11.08GR BIOS
>> to 1GB RAM using Elpida MC-4R256FKE8D-845 PC800 ECC memory RIMMs.
>> There are 4 identical modules at 256megs each which are supposed to
>> work fine as well. HP p/n is 1818-8540. (This doesn't match HP p/n for
>> XU800 accessories, though, but they should work in any PC800 eating
>> RDRAM monster).
>>
>> The machine shows "memory error" on the MaxiLife display. It also does
>> this if I put in 2 of the 128meg modules. The memory error just goes
>> away if I plug back in all 4 128meg modules.
>>
>> Is there a specific way to upgrade memory or are the modules
>> incompatible due to their specification? TIA
>
> just wanted to let everyone know that I was eventually able to get the
> system up and running.
>
> What did I do? I upgraded to BIOS 11.10US with the old RAM and then read
> the ****ing manual and found out something. I already knew that RIMMs
> need to be installed in pairs, however, I wasn't aware of how the pair
> needs to be deployed on the MEC. Once I got this right, I now have a
> XU800 with two 1GHz PIIIs and 1GB PC800-45 ECC RAMBUS memory. Together
> with two 15k Fujitsu harddisk drives, this should make for a reasonable
> fast Win2k system.
>
> Thanks anyway to both of you!
>
> Christian

yay.

Those old HP workstations are really nice machines. I'm still looking for
the fabled 8 slot memory riser for my x4000 because it's still a great
machine even though it's probaly 5+ years old now.