The BIOS ignores the memory module in the second slot

[_xyz]

I have two memory modules in the MB. the BIOS and windows ignore the module which is in the second slot.
If i swap the two modules - the BIOS recognizes the second module( which it ignored before the swap), and ignores the first.
It's strange that HW info programs do recognize the two modules:
(from PC Wizard)

General Information :
A0 (RAS 1, RAS 2) : 1024 (Double Bank)
A1 : Empty

Information SPD EEPROM (A0) :
Manufacturer : PDP Systems
Part Number : PSD1G400
Serial Number : Unspecified
Type : DDR-SDRAM PC-3200 (200 MHz) - [DDR-400]
Size : 1024 MB (2 rows, 4 banks)
Module Buffered : No
Module Registered : No
Module SLi Ready (EPP) : No
Width : 64-bit
Error Correction Capability (EC... No
Max. Burst Length : 8
Refresh : Reduced (.5x)7.8 µs, Self Refresh
Voltage : SSTL 2.5v
Prefetch Buffer : 2-bit
Manufacture : 2000
Supported Frequencies : 166 MHz, 200 MHz
CAS Latency (tCL) : 2.5 clocks @166 MHz, 3 clocks @200 MHz
RAS to CAS (tRCD) : 3 clocks @166 MHz, 4 clocks @200 MHz
RAS Precharge (tRP) : 3 clocks @166 MHz, 4 clocks @200 MHz
Cycle Time (tRAS) : 7 clocks @166 MHz, 8 clocks @200 MHz

Information SPD EEPROM (A1) :
Manufacturer : Unspecified
Part Number : 64MX64U-40B
Serial Number : 04011325
Type : DDR-SDRAM PC-3200 (200 MHz) - [DDR-400]
Size : 512 MB (2 rows, 4 banks)
Module Buffered : No
Module Registered : No
Module SLi Ready (EPP) : No
Width : 64-bit
Error Correction Capability (EC... No
Max. Burst Length : 8
Refresh : Reduced (.5x)7.8 µs, Self Refresh
Voltage : SSTL 2.5v
Prefetch Buffer : 2-bit
Manufacture : 2000
Supported Frequencies : 200 MHz
CAS Latency (tCL) : 2.5 clocks @200 MHz
RAS to CAS (tRCD) : 3 clocks @200 MHz
RAS Precharge (tRP) : 3 clocks @200 MHz
Cycle Time (tRAS) : 8 clocks @200 MHz

Memory Controller Information :
Memory Controller : DIMM
Number of connectors : 2
Max. Module Size : 1024 MB
Max. Memory Size : 2048 MB
Supported Speed : Unspecified
Supported Voltages : 3.3v
Error Detection Method : No
Error Correction Capability : None
Current/Supported Interleave : 1-way/1-way

BIOS info:

General Information :
Manufacturer : Award Software International, Inc.
Version : F9
Date : 09/10/2004 (mm/dd/yyyy)
Address : 0x0 on 256 KB
Copyright : Copyright (C) 1984-2004, Award Software, Inc.
Motherboard ID : 09/10/2004-SiS-661-6A7I4G0CC-00
OEM Signature : 8S661FXM-RZ F9
DMI Version : 2.3

What can i do to make the BIOS recognize the two modules?

 

[GhislainG]

Which one is recognized and what motherboard? The easiest solution is to buy a module that's certified to work with your system.

 

[_xyz]

The both are recognized by HW-info programs.
The BIOS and windows recognize only the module which is in the first slot (regardless of which one of the two modules it is).

 

[GhislainG]

And the motherboard is?

Did you set the timings manually in the BIOS to 3-4-4-8 to match the slowest module?

 

[_xyz]

The MB is Gigabyte 8S661FXM-RZ.
The timings are set to "auto".
If the problem was the timings, why does the BIOS ignore the slower module when it's in the second slot, and the faster module when it is in the second slot?

 

[GhislainG]

You have a point. It looks like there either is an issue with the second slot or there's an incompatibility between the modules. Does the system work if you use either module in the second slot while leaving the first slot empty? If so, then the modules probably aren't compatible.

 

[_xyz]

If i take out the module in the first slot, the BIOS beeps a long beep and refuses to boot.
the strange thing is that the slot seems to be OK, because the HW-info software recognizes it.
what may the problem be?

 

[GhislainG]

Unless that motherboard absolutely requires a module in slot 1 (that info should be in the manual), it looks like slot 2 is defective. Visually inspect it with a magnifier glass, but if nothing is visually wrong, then it's time for a new motherboard or a new system.

 

[_xyz]

Can slot 2 be defective when the memory module in it is correctly recognized by the HW-info programs?

 

[GhislainG]

Absolutely. The HW-info programs read the SPD only.