Running PC100 as PC133?

[plebeian]

How realistic is it to expect to be able to run PC100/CL2 memory at PC133 (CL3?) speed? I see lots of talk about overclocking the CPU but little about oc'ing RAM (other than via oc'ing the FSB). Does anyone do this? Is it possible or worthwhile?

The memory in question is Kingston Value RAM, the platform is: A7v+Duron.

 

[Vegito]

Probably not, being that it's value ram. Unless your MB has Memory FSB +33 or -33 option like the Apollo 133Pros.
Anyway, running PC100 @ 133 will crap it out and give you errors

 

[Fun Guy]

Only way to know is to try. I run my IBM/generic PC100 SDRAM at 112Mhz no prob (dual Celeron system, 2 x 300a @ 504Mhz). I tried it higher, but it didn't work, I don't know if it was the RAM or the Celerons, probably the CPU's.

Good luck.

 

[Train]

i get my PC100's to 112 easy, but only a few make it to 124, I havent had any make it to 133 yet. There are several brands of PC100 that have been known to get to 133 effectively, but Im not sure which ones, but ill probably look into some soon.

 

[Vegito]

I looked at the specs for good memory, most of them top off at 124Mhz, specs as in memory chip whitepaper not whats being advertise on websites.

 

[Coki]

Most of the good PC100 will do PC133.

Value RAM should work fine at 133. I had it and it worked fine. But not with two sticks of ram.

 

[AdamK47]

Back in the day of having my P3 450 at 600MHz, I used PC100 memory that made it to 133MHz easily. The Siemans PC100 memory (now known as Infineon) almost always made it to 133MHz. Right now, I'm using PC133 running at 157MHz in my 1021MHz system, so theres always room for memory to go.

 

[BurntKooshie]

<< Right now, I'm using PC133 running at 157MHz in my 1021MHz system, so theres always room for memory to go. >>

That's so untrue I have some old PC 66 32mb DIMMS. In no way can I get them to run at 75mhz. Tried changing all latencies....to no avail. I know the rest of the system can take it just fine because i had EDO DRAM in there before on a 75mhz bus.

 

[Stallion]

My Corsair PC100 which is CAS3 ran at CAS2 all the way to 120FSB and I got it to 133 at CAS3 for 2 weeks now. It has the Siemens chips.
The generic PC100 in my wifes PC though barely runs at 100.

But today my Mushkin PC133 CAS2 Rev1.5 with mosel chips came in the mail.

 

[BurntKooshie]

while i had bad PC 66, i have great PC 133. Its budget stuff PC 133 CAS 3, but it does CAS2 up to 138mhz. And CAS 3 up to 164 (that i've tested so far, and I don't know if the block was due to the ram, the CPU, or the peripherals running on a 41mhz PCI bus)

 

[masterskartrg]

my micron pc100CL2 does 138cas2 143cas3 so i guess the only way to know is try i've seen a site with this one guy whows pc100 does 198 no joke i wish i had the link others can comfirm too.he had a PIII550e @1089

 

[jebus]

Can someone point me to a tutorial about all these memory terms and configurations? Thanks!

 

[utopia]

Whooa, am i a winner? Micron High-Grade (Server!) cas3 PC100 running at 143Mhz, can do 155MHz.

 

[slaman]

wow, I guess im lucky. I can post 122 with my sh|tty noname pc100 ram...


if only my pIII 700 would hit 133 at default, i could have the 133:100 ratio working fine, and have a nice pIII 933...

 

[fu]

slaman,

the 133:100 ratio is for the back side ( memory ) bus to run at 133mhz and the front side bus to be run at 100mhz.

the memory bus isn't allowed to run below the front side bus. it can only run synchronously ( aka 3:3, 100:100, etc. ) or asynchronously ( aka 4:3, 133:100, etc. ) which will always be faster than the front side bus.

it is for systems that can't run at 133mhz fsb ( most likely because they don't have the proper pci divider ) but have memory capable of running at 133mhz.

so even if that could work for you, you cpu would still post at 700.