New RAM timings look OK except tRAS_should be 15 - shows 18

Debbie23 · Jul 14, 2011

Put in 2 new dual channel kits of 4 GB of Kingston HyperX KHX6400D2B1K2/4G (maxed at 8GB). Kingston Specs

Everything looks right in PC Wizard / CPU-Z, except for tRAS timing. Per Kingston specs, at 400 MHz (which it's at), timings at 1.8 v should be 5-5-5-15, not 5-5-5-18.

The SPDs are programmed to JEDEC standard latency 800MHz timing of 5-5-5-15 at 1.8V. Each 240-pin DIMM uses gold contact fingers and
requires +1.8V.

1.8v is the spec on this mobo & was the voltage of the OEM RAM (however, their specs were 6-6-6-18). This is an HP OEM Asus board w/ no clock settings in BIOS. I'm not sure why everything looks OK except the tRAS timing.

PC Wizard
General Information :
DIMM0 (BANK0 ) : 2048MB - DIMM
DIMM1 (BANK1 ) : 2048MB - DIMM
DIMM2 (BANK2 ) : 2048MB - DIMM
DIMM3 (BANK3 ) : 2048MB - DIMM

Information SPD EEPROM (DIMM0) :
Manufacturer : Kingston
Part Number : 2G-UDIMM
Serial Number : 353CF094
Type : DDR2-SDRAM PC2-6400 (399MHz) - [DDR2-800]
Format : Regular UDIMM (133.35 x 3)
Size : 2048MB (2 ranks, 8 banks)
Module Buffered : No
Module Registered : No
Module SLi Ready (EPP) : No
Width : 64-bit
Error Correction Capability ... No
Max. Burst Length : 8
Refresh : Reduced (.5x)7.8, Self Refreshµs
Voltage : SSTL 1.8v
Prefetch Buffer : 4-bit
Manufacture : Week 11 of 2011
Supported Frequencies : 200MHz, 266MHz, 400MHz
CAS Latency (tCL) : 3 clocks @ 200MHz, 4 clocks @ 266MHz, 5 clocks @ 400MHz
RAS to CAS (tRCD) : 3 clocks @ 200MHz, 4 clocks @ 266MHz, 5 clocks @ 400MHz
RAS Precharge (tRP) : 3 clocks @ 200MHz, 4 clocks @ 266MHz, 5 clocks @ 400MHz
Cycle Time (tRAS) : 9 clocks @ 200MHz, 12 clocks @ 266MHz, 18 clocks @ 400MHz
Min TRC : 12 clocks @ 200MHz, 16 clocks @ 266MHz, 23 clocks @ 400MHz

TechSpot

New RAM timings look OK except tRAS_should be 15 - shows 18

Debbie23 Newcomer, in training

Attached Files:

CPU-Z Mem tab_2011-07-15.png