RAM not detected on my laptop?

**Elvenmunky** · 05-23-2007, 10:53 AM

i put the ram in both slots and windows system, bios and ccleaner and crucial system scanner (where i bought it off) says 384mb of ram even tho i bought another one and put that in. chek this...do i need to enable the ram or something?

with both newand old ram pc wizard gave me this (overview says 1gb ddr2 ram)...

General Information :
DIMM0 (RAS 0, RAS 1) : 512 (Single Bank)
DIMM1 : Empty

Information SPD EEPROM (DIMM0) :
Manufacturer : Micron Technology
Part Number : 4HTF6464HY-667E1
Serial Number : D21A2562
Type : DDR2-SDRAM PC2-5300 (333 MHz)
Format : SO-DIMM (67.6 x 3)
Size : 512 MB (1 ranks, 8 banks)
Module Buffered : No
Module Registered : No
Module EPP : No
Width : 64-bit
Error Correction Capability : No
Max. Burst Length : 0
Refresh : Reduced (.5x)7.8 µs, Self Refresh
Voltage : SSTL 1.8v
Prefetch Buffer : 4-bit
Manufacture : Week 24 of 2007
Supported Frequencies : 200 MHz, 266 MHz, 333 MHz
CAS Latency (tCL) : 3 clocks @200 MHz, 4 clocks @266 MHz, 5 clocks @333 MHz
RAS to CAS (tRCD) : 3 clocks @200 MHz, 4 clocks @266 MHz, 5 clocks @333 MHz
RAS Precharge (tRP) : 3 clocks @200 MHz, 4 clocks @266 MHz, 5 clocks @333 MHz
Cycle Time (tRAS) : 9 clocks @200 MHz, 12 clocks @266 MHz, 15 clocks @333 MHz
Min TRC : 12 clocks @200 MHz, 16 clocks @266 MHz, 20 clocks @333 MHz

Information SPD EEPROM () :
Manufacturer : Infineon
Part Number : 64T64020HDL3.7A
Serial Number : 020A5812
Type : DDR2-SDRAM PC2-4300 (266 MHz)
Format : SO-DIMM (67.6 x 3)
Size : 512 MB (2 ranks, 4 banks)
Module Buffered : No
Module Registered : No
Module EPP : No
Width : 64-bit
Error Correction Capability : No
Max. Burst Length : 0
Refresh : Reduced (.5x)7.8 µs, Self Refresh
Voltage : SSTL 1.8v
Prefetch Buffer : 4-bit
Manufacture : Week 40 of 2006
Supported Frequencies : 200 MHz, 266 MHz, 266 MHz
CAS Latency (tCL) : 3 clocks @200 MHz, 4 clocks @266 MHz, 5 clocks @266 MHz
RAS to CAS (tRCD) : 3 clocks @200 MHz, 4 clocks @266 MHz, 4 clocks @266 MHz
RAS Precharge (tRP) : 3 clocks @200 MHz, 4 clocks @266 MHz, 4 clocks @266 MHz
Cycle Time (tRAS) : 9 clocks @200 MHz, 12 clocks @266 MHz, 12 clocks @266 MHz
Min TRC : 12 clocks @200 MHz, 16 clocks @266 MHz, 16 clocks @266 MHz

Memory Controller Information :
Memory Controller : System Memory
Location : Mainboard
Error Correction Capability : No
Number of connectors : 2
Max. Module Size : 1024 KB

and then when im took one ram out (overview now says 512 ram) it gave me this...

General Information :
DIMM0 : Empty
DIMM1 (RAS 2, RAS 3) : 512 (Double Bank)

Information SPD EEPROM () :
Manufacturer : Infineon
Part Number : 64T64020HDL3.7A
Serial Number : 020A5812
Type : DDR2-SDRAM PC2-4300 (266 MHz)
Format : SO-DIMM (67.6 x 3)
Size : 512 MB (2 ranks, 4 banks)
Module Buffered : No
Module Registered : No
Module EPP : No
Width : 64-bit
Error Correction Capability : No
Max. Burst Length : 0
Refresh : Reduced (.5x)7.8 µs, Self Refresh
Voltage : SSTL 1.8v
Prefetch Buffer : 4-bit
Manufacture : Week 40 of 2006
Supported Frequencies : 200 MHz, 266 MHz, 266 MHz
CAS Latency (tCL) : 3 clocks @200 MHz, 4 clocks @266 MHz, 5 clocks @266 MHz
RAS to CAS (tRCD) : 3 clocks @200 MHz, 4 clocks @266 MHz, 4 clocks @266 MHz
RAS Precharge (tRP) : 3 clocks @200 MHz, 4 clocks @266 MHz, 4 clocks @266 MHz
Cycle Time (tRAS) : 9 clocks @200 MHz, 12 clocks @266 MHz, 12 clocks @266 MHz
Min TRC : 12 clocks @200 MHz, 16 clocks @266 MHz, 16 clocks @266 MHz

Memory Controller Information :
Memory Controller : System Memory
Location : Mainboard
Error Correction Capability : No
Number of connectors : 2
Max. Module Size : 1024 KB

its not faulty ram coz i tried both old and new in both slots and they worked each time. anyone got any suggestions...its an A6RP ASUS notebook.

**lynx** · 05-23-2007, 12:49 PM

Memory is generally arranged in one of a two ways: single and dual ranks. You can also get dimms with 4 ranks, but they aren't common.

On some systems you can't mix single rank and dual rank memory sticks, and that's what you've done:
DIMM0 (RAS 0, RAS 1) : 512 (Single Bank)
DIMM1 (RAS 2, RAS 3) : 512 (Double Bank)

It used to be that single sided dimms had a single rank and double sided dimms had dual rank. But that's not always the case any more, particularly on SODIMMs.

You will need to exchange one of the memory sticks for one that it matches the layout of the remaining stick.

I also notice that the sticks have different speeds. That's not a good idea either, but it is unlikely to be causing this particular problem.

Best thing when adding more memory is to match the existing memory as closely as possible.