EDO RAM?

[gyoung]

I have an old Pentium 166 IBM Aptiva that my fiance is using. It has 32MB of memory in it. This machine isn't a screamer and doesn't need to be. She uses it for general surfing and Word processing. The problem really is that their isn't enough RAM. You can hear the swap file going on and on and on...

I want to upgrade the RAM. According to the manual and the IBM website it uses this RAM:



<<
Aptiva 2161 C8E Support
Product Description
P166 MMX(256KB) 32MB 3.1GB HDD IDE PCI/ISA Minitwr(7X6) ATI 16X CD 33.6K Win95

Memory
Soldered 0
Number of Sockets 2 DIMM

Type 168-pin SDRAM DIMM (gold)

Maximum 64 MB
Speed 60 ns
Voltage 3.3V
Wait States n/a
Memory Sizes 16, 32 SDRAM DIMMs

ECC Support n/a
Parity No
RAM on Adapter No
FlexMemory (UMA) No
>>



Is this EDO memory? I think it is. Do I have to buy EDO or will regular PC66 or PC100 DIMMs work?

I want to buy 2 32MB DIMMs to max out the memory. It currently has 2 16MB DIMMS.

 

[Biggs]

The specs ya posted are for SDRAMs.

 

[AndyHui]

Type 168-pin SDRAM DIMM (gold)

Maximum 64 MB
Speed 60 ns
Voltage 3.3V
Wait States n/a
Memory Sizes 16, 32 SDRAM DIMMs

That says SDRAM to me. Nowhere does it say EDO RAM, and it tells you the sizes of the DIMMs it can take. If you want 64MB of RAM, you will need 2 32MB DIMMs. PC66 SDRAM should work, although you should open up your system: all SDRAM today is 3.3 volts....but some older DIMM slots require 5 volt DIMMs.

 

[gyoung]

For some reason I thought the part about the ECC = n/a meant EDO. But that makes it easier. EDO is a lot harder to find and more expensive!

Where would a good place be to find this type of RAM? When I search on www.pricewatch for 60ns it gives me EDO and FPM. I never see any pc66 RAM. I guess this is why I assumed it was EDO.

 

[Biggs]

ECC (Error Correction Coding) is as it says used to correct errors that may occur. It's more expensive than &quot;standard&quot; RAM but if you need stability, go with ECC which takes a slight performance hit btw.

 

[Priit]

What chipset does that Aptiva have ? It may requie some exotic memory (like buffered DIMM's). Also check that you have free memory slot before buying anything, I've seen Aptiva with 4x4Mb of RAM for 16Mb...

 

[gyoung]

There are two memory DIMM slots with each being occupied by a 16MB DIMM (for a total of 32MB).

I looked up the info on the Aptiva 2161 and it is using the Intel 430VX chipset which is a form factor of LPX with Riser.

 

[gyoung]

This comes from the Aptiva 2161 product description.



<<
Two, 168-pin Gold, EDO, Unbuffered, Synchronous Dynamic Random Access Memory (SDRAM) DIMM module sockets.

Depending on model, 16 MB or 32 MB of system memory is supplied. Maximum system board memory is 64 MB.
Ports: serial, USB (Universal Serial Bus), parallel, keyboard, mouse, and video.
>>

 

[AndyHui]

The Intel 430VX chipset will take standard 3.3 volt DIMMs. PC100 SDRAM should work. The PCxxx specification simply states a guaranteed maximum speed the RAM will run at.

It won't be necessary to purchase ECC SDRAM for this system.

 

[gyoung]

I've been poking around Intel's website trying to find the motherboard. I can't find it. Would you know what motherboard this is?

==================

Found it, but it is archived and it doesn't have the necessary information.

 

[AndyHui]

You won't find details about that specific motherboard at Intel. IBM uses proprietary in-house designs for their Aptiva systems (and just about every other IBM system).

If you want to find technical details about the 430VX chipset, you are about 2 months too late. Intel withdrew all support including web documentation for this chipset at the beginning of December 2000...

 

[Priit]

I have computer featuring VX chipset at home, It detects 64Mb (8Mx64) DIMM as 16Mb...

 

[gyoung]

I have been looking around the IBM and Intel sites to find some information. The IBM site says that the chipset is the 430VX. I went to the Intel site and this is so old that they archived the information.

From what I can tell, it can take EDO or SDRAM. Here is some info that I found on SysOpt:

http://sysopt.earthweb.com/intelch5.htm#430vx

The manual of the Motherboard says max of 64MB, the info here at sysopt says max of 128MB.

Should I take my chances and get some PC66 or PC100 memory and see if it works?

I have a 64MB PC133 stick that I could check also.

This is from the last known issues page from Intel:



<<
Abstract: This document describes why 430VX does not support x4 SDRAM configuration.

Problem: There have been questions regarding 430VX chipsets working with 4M x4 SDRAMs.


Solution: The SDRAMs, due to their synchronous nature, put extra pressure on meeting timing specifications. Specifically at 66MHz (15ns clock period), the clock skew and Hclk signal integrity become major issues. Consequently, it is purely a loading/timing reason why we cannot support x4 SDRAMs. We do support x8 or x16 SDRAMs because now loading is halved.

Future chipsets are heading for higher speeds and will be even harder to meet the timings. In summary, 430VX can drive 8 loads per row. This sets our lower limit at x8.
>>



So maybe the chips need to be 4x8 or 4x16 to be detected correctly?

 

[AndyHui]

Although the VX chipset can support up to 128MB of RAM, it can only cache 64MB. There is a limit on the amount of RAM that the VX can address through DIMM slots as well.....64MB is the maximum if I remember correctly. It is able to address more through SIMM slots.

 

[gyoung]

Then I guess the question is this:

What type of memory would be the best to take a chance on? (eg: PC66, PC100)

And should I look at specific densities? (eg: 4x8, 4x16, 4x64)

OR

Would a 32MB upgrade to a full 64MB really see any performance increase or am I just wasting my time? (I think it would)

The PC is running Windows 98. The primary uses again are: Windows 98, Office 2000, and IE.

 

[gyoung]

^^