Do Recent PC133 Memories Not Work As PC100?!

[Kenji4861]

I was about to buy a K-BYTE 256mb PC133 for a friend until someone told me the recent K-BYTE/PNY/KINGSTON rams use a special high density format so we can't run it as PC100 on many motherboards.


IS THIS TRUE?!

 

[murphy55d]

this would likely be better suited for general hardware.

i don't know the answer to your question though... i have not heard of that myself, but i haven't used pc133/100 in quite some time.

 

[Woodchuck2000]

The issue, I believe, is that double sided modules will not work on older motherboards. It's all backwards compatible with PC100 and PC66 but you should check that it's compatible with your motherboard.

 

[PG]

That is very true. It isn't backwards compatible anymore.

Older BX chipset type computers will either not recognize the memory at all or recognize half of it.

 

[radioouman]

I've heard this, but I highly doubt it. I would guess since 90% of all systems that use SDRAM had a 100 MHz bus (or 66 MHz), the memory companies are trying to get you to buy PC100 at a higher cost.....

EDIT: I stand corrected.

 

[Iron Woode]

Originally posted by: Kenji4861
I was about to buy a K-BYTE 256mb PC133 for a friend until someone told me the recent K-BYTE/PNY/KINGSTON rams use a special high density format so we can't run it as PC100 on many motherboards.


IS THIS TRUE?!

Double sided or not is not the issue. It is the ram density of the ram chips that matter.

Most older chipsets ie LX, Via MVP3, etc cannot support high density ram. They only see half of it.

I think (not sure) that the BX chipset does not support it.

 

[minendo]

Many of the newer pc133 sticks do not downclock to PC100. This is why they do not work in pc100 configurations.

 

[Woodchuck2000]

Originally posted by: minendo
Many of the newer pc133 sticks do not downclock to PC100. This is why they do not work in pc100 configurations.

You got any links for that? I was fairly sure that it was simply an issue of the memory density stopping older boards recognising it (That or issues with PCs needing 2-clock SDRAM.)

 

[Zim Hosein]

Taken from PNY's FAQ's:

Q: Are PC133 modules backward compatible with PC100 machines?

A: No, PC133 modules are NO LONGER backward compatible with PC100 machines.

PC 133 modules are now made with the latest, high density chip technology. Older systems may not be compatible with this technology.

 

[Iron Woode]

Originally posted by: Zim Hosein
Taken from PNY's FAQ's:

Q: Are PC133 modules backward compatible with PC100 machines?

A: No, PC133 modules are NO LONGER backward compatible with PC100 machines.

PC 133 modules are now made with the latest, high density chip technology. Older systems may not be compatible with this technology.

But the ram modules can be run at 100mghz.

I have a Duron set up using PC133 at 100mghz (FSB 200mghz) and all is fine.

 

[Zim Hosein]

Taken from the Kingston FAQ's:

Kingston 133 MHz ValueRam modules are manufactured according to current memory technology standards. Unfortunately not all computer systems can handle this technology. The 133MHz ValueRam modules use memory chips that have a density of 256 megabits per chip. Some older computer systems are only equipped to read up to 128 megabits on the chips. Therefore these systems can only see half of the actual memory capacity. If your motherboard is using a BX, ZX, or 810 chipset you will need a module built with memory chips that have a maximum density of 128 megabits.

 

[RossMAN]

I remember when 256MB PC133 SDRAM for $70 each from Crucial.com was a GOOD PRICE 🙁

Now you can get it for free after rebate during one of the holiday rebate sales 🙁

 

[bozack]

I think older PC133 sticks were in fact backwards compatable, however with technology progressing as it is they saw no need to contuinue this which might have increased their production costs and limited performance...