What are the odds of getting PC100 to run at PC133?

[MichaelD]

As above. Before I start tearing stuff up and possibly blowing it up, I thought I'd ask. I think the answer is "no way in hell!" AM i correct?

 

[MichaelD]

<< Most of good quality PC100 RAM can run at 133FSB w/o probs. I mean Micron, Samsung, Hyundai modules etc. If they're rated for 8ns they should work fine. >>




Hmm, that's good to know. I have 512mb of PC100 that has a "Dell" sticker on it; I bought for my old Dell PIII550e. The memory is actually Samsung brand chips that have an "8" printed on them.

I want to mix the PC100 with some PC133 (building another box and too cheap to buy PC133...especially at what it costs these days.) Thanks, Geared.

 

[Colt45]

Most decent ram can make it, but say..

you OC some PC100 CAS2 to 133FSB, it will most likely run at CAS3/133

now if youve got some generic CAS3 PC100, your odds of OC'ing it isnt great

 

[Adul]

<< Most decent ram can make it, but say..

you OC some PC100 CAS2 to 133FSB, it will most likely run at CAS3/133

now if youve got some generic CAS3 PC100, your odds of OC'ing it isnt great >>




pretty much try it and see.

 

[MichaelD]

<< Most decent ram can make it, but say..

you OC some PC100 CAS2 to 133FSB, it will most likely run at CAS3/133

now if youve got some generic CAS3 PC100, your odds of OC'ing it isnt great >>




I neglected to take that into consideration. I like my CAS2. Much snappier, IMO. Thanks for pointing that out.

 

[Rand]

I'd say a lot of it depends when it was manufactured, early PC100 DIMM's generally overclocked extremely poorly.
Compared to late in the life-time of PC100 DIMM's in which basically even the poorest spec Cas3 PC100 DIMM could do at the very least 124MHz.

I've got a stick of generic 256MB Cas3-3-3 rated PC100 SDRAM that is rock solid at 164MHz memory bus at Cas2.... that DIMM was manufactured a few months before DRDRAM first appeared.. quite late in the life-span of SDRAM. On the other hand I've got a stick of Micron 128MB Cas2 PC100 SDRAM that will only do 115MHz at Cas3. It was manufactured shortly after JEDEC ratified the PC100 spec.

 

[Modus]

Rand is right. Age is the most important factor in predicting whether a PC100 DIMM will make it to 133 MHz. As a rule of thumb, most PC100 DIMMS made after Y2K were in fact fully capable of a PC133 designation but were marked PC100 for marketing purposes so that buyers with 100 MHz mainboards would purchase them. Even today, some hardware enthusiasts are unaware that a PC133 DIMM will run reliably at 100 MHz.

As others have said, 133 MHz CAS3 is much more attainable than 133 MHz CAS2.

Modus

 

[MichaelD]

Thanks, Rand and Modus (I haven't seen you two post in a looong time...maybe I've been in OT too long?)

I have no way of telling when my PC100 sticks were manufactured. Upon closer inspection, they are Micron, not Samsung as I had originally thought (the chips themselves are stamped with a funny-looking "MT") and they have a "Dell" sticker on them. I haven't actually looked at the things in a couple of years.

One stick came with my Dell. (Stop laughing...we all were "newbs" once! ) The other stick I ordered from Dell *snicker-snicker* by entering in my "Service Tag" *Bwuahahahahahahahahaha!* on their site back in 1999. The two sticks actually have really close serial numbers (on the white "Dell" stickers) so are prolly from the same batch.

We'll see what happens. I have a crappy stick of Samsung PC133 that will do 133/CAS2 but God help you if you try and raise it past 138MHz or so....the PC100 should be comfy with that stick.

Thanks much.

 

[DayLaPaul]

if you look on the chips, there should be a 4 digit number that tells you when the chip was manufactured. the actual module would most likely have been produced a short time afterwards. example: 9933 means, year 1999 33rd week.

 

[McCarthy]

Agreed on the age thing. Bought myself a stick of Toshiba (recommended around here at the time) PC-100 SDRam, 128 meg, $200. This to go with my Celeron 300A to run at 450. It never did 450, I figured it was the chip.

Upon buying some more ram later and giving it another go I found this 8ns rated PC-100 ram won't even do PC-100, works great at 66 though. Still in my spare computer, lil celeron 600 I just use to watch DIVX movies on. Way way too late to do anything about it though once I found out. Oh well.

In the end, gotta try it to know for sure though.

--Mc

 

[ChrisIsBored]

I've sold some PC-100 Kingston ValueRAM here on the forums, recently someone I sold a stick to way back in December created a thread saying he got his PC-100 oc'd to PC-150.

Just depends on the quality of RAM you're using...

 

[MasterHoss]

I tried it a long time ago (when I first go my ASUS A7V133 mobo and was waiting for my CAS 2 PC133 SDRAM from Crucial), I successfully got my Crucial PC100 CAS2 SDRAM to run at 133MHz at CAS3.

 

[Jhhnn]

If the memory is pc100 cas2, then it will definitely run 133cas3. The math's been posted many times, it will actually be running slower, IIRC....