Memory questions...

[ahartman]

I'm planning on buying another 128M of memory and I've got a question or two...

I'm planning on getting it from Crucial; here's what I'm getting:

128M SDRAM PC133 (part # CT16M64S4D75).

I've got 128M of, I belive PC100, which I'm going to eventually replace.

My questions are:

1) There's no mention of CAS2/CAS3 - I've seen this bandied about and I'm not sure how to tell one from the other. Does it matter?

2) I may start overclocking my computer in the near future - what should I think about with respect to the memory I buy now?

3) I have an IWILL VD133 mobo and my P3 is running at 550 (100x5.5). Does this mean my entire bus is running at 100MHz or that my CPU is talking to the bus at 100MHz? I know the board has a 133MHz bus. Am I wasting money by getting PC133 memory if my bus is only running at 100?

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PIII 550 (not O/C'ed)
IWill Motherboard 133
VIA Chipset
128Meg RAM
G400 DH 32MB (5.41 Drivers)
DirectX 7.0
SB Live! Value
8x DVD (Toshiba)
6x4x24 CDRW (Sony)
Optiquest V95 19"
HP 812C Color Ink Jet
Microtek flatbed scanner
Intellimouse Explorer
Surround Sound w/two subwoofers
AND WAY TOO MANY GAMES!!!

[paulcs]

I have a stick of Crucial PC133 RAM and it's rated at CAS2. If you're thinking of overclocking that PIII 550E, I think CAS2 PC133 RAM is a fine choice.

Your front side bus is most likely running at 100 MHz. If you overclock your CPU, it won't be, so your RAM will probably have to exceed the PC100 spec.

There's one fly in the ointment. Many of the new VIA chipsets allow your RAM to run asynchronously from your CPU. That is, you have the option to run your CPU at 133 MHz and your RAM at 100 MHz and visa versa. I know the VIA Apollo Pro 133A and the KX133 chipsets have this feature. I'm not sure if that's the case with your IWILL board. I think if your overclock your CPU, you will most likely be overclocking your RAM.

I found Crucial PC133 DIMMs to be not a whole lot more than their PC100 rated RAM. It's guaranteed to run at 133 MHz and will most likely run higher. It could give you a lot more flexibility when overclocking.

Paul
paulcs@flashcom.net

[This message has been edited by paulcs (edited 21 March 2000).]

[Wombat]

That's CAS3 stuff. If you're thinking about OC'ing, go for the xxxxx7E stuff. That's their CAS2, and it has a better shot at reaching 150MHz.

[Mark F]

The current price difference between the CT16M64S4D75(CAS3@133/I was able to run it at 3-2-2) and the CT16M64S4D7E(CAS2@133/I run it at 2-2-2), is only $12US. However, at 100MHZ FSB both will run at CAS2.

Mark F.

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OH NO, my retractable cup holder swallowed a DVD...
and burped out a movie




[This message has been edited by Mark F (edited 22 March 2000).]

[paulcs]

Sorry, I should have looked at the part number carefully.

Paul
paulcs@flashcom.net

[paulcs]

How extreme is this overclock going to be? By all means take Wombat's and Mark's advice and go for the CAS2. I'm just curious. People are doing some nutty stuff with the 550E.

Paul
paulcs@flashcom.net

[ahartman]

I don't know how much I'll overclock - I've never tried and it would be as much for education as for speed.

Looking thru BIOS, it looks like I have the following simple options to overclock (from memory, forgive if incorrect):

multiplier: 2-8 (.5 increments)
Bus speed: 100-124 (in 3 MHz increments)

I'd probably punk out before I had to get too crazy with cooling things inside the PC but who knows...

Other posts have said CAS3@133 is faster/better than CAS2@100 (of course, I'm assuming CAS2@133 is the best option...) but that CAS2 vs. CAS3 isn't that big of a deal (2%). I'm not so pressed for speed that I'm necessarily caring about that extra 2-3%.

One other thing - I went thru the MB maker/type dropdowns and the 7E memory wasn't one of the options they gave me - does that mean it won't work in my PC?

Thanks for the help guys!

Andy

[Mark F]

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Other posts have said CAS3@133 is faster/better than CAS2@100 (of course, I'm assuming CAS2@133 is the best option...) but that CAS2 vs. CAS3 isn't that big of a deal (2%). I'm not so pressed for speed that I'm necessarily caring about that extra 2-3%.
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The extra MHZ will always give you a greater boost than CAS2 vs CAS3. So, go for the speed. Before 133MHz buss and memory, it was more of an issue,as you could resonably expect PC100 CAS2 memory to run at higher speeds than PC100 CAS3; you had the headroom of droping down to CAS3 to get it to run.

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One other thing - I went thru the MB maker/type dropdowns and the 7E memory wasn't one of the options they gave me - does that mean it won't work in my PC?
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I probably wouldn't worry about that. Under my MB non of the PC133 are listed; But both -75 and -7E have worked fine. Use the advanced search and go to 168pin DIMMS at the bottom you will see all the PC133 moduals (and PC100 above it).

Good Luck,
Mark F.



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OH NO, my retractable cup holder swallowed a DVD...
and burped out a movie

[ahartman]

Just pushed the order button on the CAS2 PC133 from Crucial. Should have it by Tuesday!

Now I gotta determine if my current stick of memory stays or gets replaced by another one from Crucial...