Q: How to correctly determine/set CAS latency in BIOS?

[Mr. X]

This is what I got. My question follows.


= RAM =

1 DIMM, 256 MB
8 per side, ID: "Hyundai GM72V28841ET75",


= Sandra =

Mainboard
Manufacturer : AZZA Technology
MP Support : No
Model : i810-47B27X
System BIOS : 03/16/2000-i810-47B27X-6A69MP8DC-00
Chipset : Intel 810 (Whitney)

FLASH Memory Controller
Location : Mainboard
Error Correction Capability : None
Number of Memory Slots : 4
Bank0/1 - A0 : DIMM 256MB/64
Bank2/3 - A1 : Empty
Bank4/5 - A2 : Empty
Bank6/7 - A3 : Empty

Chipset 1
Model : Intel Corporation 82810 810 Chipset Memory Controller Hub
Front Side Bus Speed : 1x 100MHz (100MHz data rate)
Maximum FSB Speed / Max Memory Speed : 1x 100MHz / 1x 100MHz
Width : 64-bit
IO Queue Depth : 4 request(s)

Logical/Chipset 1 Memory Banks
Bank 0 : 128MB SDRAM 2-3-3-0
Bank 1 : 128MB SDRAM 2-3-3-0
Shared Memory : 1MB
Width : 64-bit
Refresh Rate : 15.60µs
Power Save Mode : No
Fixed Hole Present : No

Memory Module 1
Type : 256MB SDRAM
Technology : 16x(16Mx8)
Speed : PC133U 3-3-3-5
Version : 2.0
Date of Manufacture : zaterdag, 25 december 1999
Set Timing @ 133MHz : 3-3-3-5

= BIOS SETTINGS=

Given the above info, which following settings should I use in the BIOS?


Advanced Chipset options:

SDRAM CAS Latency Time : 2, 3
SDRAM CAS Time Tras/Trc : 5/7, 6/8
SDRAM RAS-to-CAS Delay : 2, 3
SDRAM RAS Precharge Time : 2, 3
CPU Latency Timer : on, off
Delayed Transaction : on, off
On-chip Video Windows size : 64MB, off


Frequency/voltage Control options:

Spread Sprectrum : 0.50%, 0.75%, off


Thanks.

PS: Email is fake, please post your valuable knowledge in this thread.
==
M.T.

 

[George Macdonald]

This is what I got. My question follows.


= RAM =

1 DIMM, 256 MB
8 per side, ID: "Hyundai GM72V28841ET75",

Note that this is actually a LGSemi part, which I guess is now listed under
Hundai since the merger a few years ago... and LG did not stand for "Life
is Good" back then... but Lucky Goldstar.

= Sandra =

Mainboard
Manufacturer : AZZA Technology
MP Support : No
Model : i810-47B27X
System BIOS : 03/16/2000-i810-47B27X-6A69MP8DC-00
Chipset : Intel 810 (Whitney)

FLASH Memory Controller
Location : Mainboard
Error Correction Capability : None
Number of Memory Slots : 4
Bank0/1 - A0 : DIMM 256MB/64
Bank2/3 - A1 : Empty
Bank4/5 - A2 : Empty
Bank6/7 - A3 : Empty

Chipset 1
Model : Intel Corporation 82810 810 Chipset Memory Controller Hub
Front Side Bus Speed : 1x 100MHz (100MHz data rate)
Maximum FSB Speed / Max Memory Speed : 1x 100MHz / 1x 100MHz
Width : 64-bit
IO Queue Depth : 4 request(s)

Logical/Chipset 1 Memory Banks
Bank 0 : 128MB SDRAM 2-3-3-0
Bank 1 : 128MB SDRAM 2-3-3-0
Shared Memory : 1MB
Width : 64-bit
Refresh Rate : 15.60µs
Power Save Mode : No
Fixed Hole Present : No

Memory Module 1
Type : 256MB SDRAM
Technology : 16x(16Mx8)
Speed : PC133U 3-3-3-5
Version : 2.0
Date of Manufacture : zaterdag, 25 december 1999
Set Timing @ 133MHz : 3-3-3-5

= BIOS SETTINGS=

Given the above info, which following settings should I use in the BIOS?


Advanced Chipset options:

SDRAM CAS Latency Time : 2, 3
SDRAM CAS Time Tras/Trc : 5/7, 6/8
SDRAM RAS-to-CAS Delay : 2, 3
SDRAM RAS Precharge Time : 2, 3

Does your BIOS Setup not have Auto settings to use the SPD info? If it
does it would be a good idea to see what it makes of it first before
fiddling with things. If you have no other way to find out current
timings, memtest86+ (www.memtest.org) usually shows it for chipsets I've
used.

Maybe you're confused because you have a DIMM capable of PC-133 operation
but you're running it at 100MHz? Based on the info shown above I'd try
Tcl=2, Trcd=3, Trp=3 & Tras=5 and run some tests to see if it's stable; tCL
at 2 *might* be pushing it a bit, especially with more than one DIMM in the
system

CPU Latency Timer : on, off
Delayed Transaction : on, off

I believe those are PCI Bus settings and you can safely turn both on unless
maybe you have an old PCI card.

On-chip Video Windows size : 64MB, off

If you don't have a separate video card, leave this at 64MB, otherwise set
to zero. If you have 256MB total memory with just that one DIMM and don't
do anything which needs the extra video memory, you can likely get by by
setting it to 32MB.

Frequency/voltage Control options:

Spread Sprectrum : 0.50%, 0.75%, off

This just dithers the system clock, supposedly for RFI reasons. I always
turn it off, figuring I'll enable it if I need it.