G6-266 Only Recognizes Half (64MB) of Installed Memory Upgrade (128MB)

I have a G6-266 running Windows98SE with a PD440FX motherboard. It
came with 32MB of RAM, but I upgraded some time ago to 64MB total
(4x16MB SIMMS)with no problems. I recently ordered 2x64MB SIMMS
(after making sure it met the specs for my system: EDO, non-parity, 72
pin, 60ns DRAM). When I installed the RAM and rebooted, my system
only recognized 64MB total instead of 128MB. If I add in some of my
old memory, I can get it up to about 96MB, but it should be about
160MB. I tried running a utility to identify system characteristics,
and it says I have 2x32MB installed instead of 2x64MB. Anyone else
run across this with a G6-266?

Some additional info on my system: BIOS is AMIV BIOS v1.00.01.DTOT.
I cannot find a Gateway upgrade for this BIOS, but did find where
Intel has a .09 version which does mention a change to slow the system
clock when using 64MB SIMMS. Don't know if this would solve my
problem or not, and unfortunately, the Intel upgrade will not load on
my machine. Anyone know if a Gateway upgrade is available? I've read
of some ways of using the Intel upgrade, but am leary of this since a
screw up is potentially catastrophic.

One other item I ran across, but haven't been able to confirm for my
situation is that some motherboards will only recognize half of the
installed RAM if its refresh rate is double what the board can handle.
The RAM I bought has a 4K refresh rate, but I can find no information
on what my system/board can handle. Don't know if this might be
related to the BIOS upgrade above.

Again, any tips from anyone running into this same problem would be
appreciated!

Thanks,
Joe

 

It sounds like the memory is built on chips that are too dense for that
relatively old chipset - a BIOS update (there is none from Gateway) will
likely not help.

 

Thanks for the reply, Edward. If the "newness" of the memory is the
problem, does anyone have any ideas on where to find "older" SIMMs
that would work? Any recommendations on websites?

Thanks,
Joe

 

Given the cost of the RAM, I'd look for a used PIII board and processor --
you can find complete PIII 500 systems going for $100 or less now - you
should be able to pick up a Gateway board and PIII CPU for well under that,
and just use standard, inexpensive SDRAM.

I wouldn't invest much in an old PII system that's not worth much more than
$50 on the used market - if that.

 

Intel's PD440FX manual contains the following description, lifted out with
Acrobat Reader 4.0. Note that there is no reference to memory clocks, but some
newer EDO memory may have been built to clock faster than the board handles,
leading to half-recognition of the memory capacity. But, for sure, 4x64MB SIMMs
are an allowable setup.

One other comment: This board, being one of the earliest Pentium II boards, is
just a little bit quirky about accepting faster (up to 533MHz) Celeron
processors using a Slotket. My suggestion is to not go there. I concur with
Edward's suggestion of replacing the board with an inexpensive Pentium 3 or fast
Celeron (even up to 1.4GHz in some boards) combo. However, be advised that you
will probably have to retrofit a more modern I/O shield to deal with the
different layout of external motherboard connectors in the back of the case.

.... Ben Myers

Excerpt from Intel spec:
The motherboard has four SIMM sockets arranged in two banks: bank 0 and bank 1.
Each bank has two sockets and provides a 64/72-bit wide data path. SIMMs in the
same bank must be the same type (EDO, nonparity, parity, ECC), size, and speed;
SIMMs in different banks may differ in type, size, and speed. SIMMs must be
installed in both sockets of a bank, and at least one bank must be filled for
the motherboard to work. The minimum memory size is 8 MB, and the maximum size
is 256 MB. The BIOS automatically detects memory type and size, so no jumper
settings are required.
The motherboard supports the following:
· 72-pin SIMM modules with tin-plated contacts only
· 50 ns or 60 ns DRAM speed only
· EDO SIMMs only
· Nonparity, parity, or ECC SIMMs
· 5 V-memory only
· Single- or double-sided SIMMs
The motherboard supports SIMMs in the following sizes:
Table 1. SIMM Sizes and Configurations
SIMM Size Nonparity Configuration Parity and ECC Configuration
4 MB 1 x 32 1 x 36
8 MB 2 x 32 2 x 36
16 MB 4 x 32 4 x 36
32 MB 8 x 32 8 x 36
64 MB 16 x 32 16 x 36

1.7.1 EDO DRAM
EDO DRAM improves memory-read performance by holding the memory data valid until
the next falling edge of the CAS# signal. With EDO DRAM, the CAS# precharge
overlaps the data-valid time, which allows the CAS# signal to negate earlier
while still satisfying the memory data-valid window.

1.7.2 Parity/ECC DRAM
Memory error checking and correction supports the following operations:
· Parity memory operation¾detects single-bit errors but does not correct the
errors.
· Error checking and correcting (ECC) operation¾detects single-bit and
double-bit errors, and corrects single-bit errors.
Use parity and ECC memory as follows:
· Parity and ECC SIMMs must not be mixed in the same bank.
· The 82441FX (PMC) memory controller automatically detects the presence of
parity and ECC SIMMs (36-bit modules) and treats them identically.
· Parity and ECC operations are supported with parity or ECC SIMMs.
· Use the Setup program to enable parity or ECC support. See Section 4.2.32 for
information about enabling parity or ECC support.
· If any nonparity SIMMs are installed, the memory operates in nonparity mode
only. The Setup options for selecting parity or ECC mode do not appear.
The following table describes the effect of using Setup to put each memory type
in each supported mode. Whenever ECC mode is selected in Setup, some loss in
memory performance occurs.

Table 2. Memory Error-Detection Modes in the Setup Program
SIMM Type Disabled Parity ECC
Nonparity SIMMs No error detection N/A N/A
Parity SIMMs No error detection Single-bit error detection Single-bit error
correction, double-bit error detection
ECC SIMMs No error detection Single-bit error detection Single-bit error
correction, double-bit error detection