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EchoWars
31st May 2001, 16:09
Using Windows 2000 with a Epox EP-MVP3C2 motherboard and a K6-2+ 550MHz processor. I need someone to set me straight on a few thngs. The system right now is running with 128Mb of SDRAM. The motherboard has only 512K of L2 cache. If I remember right, with 512K of L2 cache, the system can only cache 128Mb of system memory (please correct me if I am wrong...!!). Now, the processor, being a K6-2'+' series, has 128K of built-in L2 cache, effectively making the motherboard cache a 'L3' cache. Sooooooooo...

1. How much RAM can the system cache?

2. Does the built-in L2 cache on the K6-2+ have any effect on the amount of cacheable RAM?

3. What happens when physical memory exceeds the amount of cacheable RAM, and does using W2K affect this in any way?

I have actually sent a couple of emails to AMD and never heard back...bloody wankers!!

Thanks Guys!!!!! http://forums.murc.ws/ubb/biggrin.gif

Greebe
31st May 2001, 17:01
I was thinking that 512k cached 64megs and 1meg cached 128megs, but that portion of me brain has too many cobwebs init.

Greebe
31st May 2001, 17:03
2. no... the L2 now L3 is what detiremines what amountis cachable

3. I dunno

Rags
31st May 2001, 17:38
1. The amount of RAM a system can cache on a system with onboard cache is determined by the motherboard itself. The general rule is that 64 megs can be cached with 256K, 128 with 512, etc. BUT it can differ. Refer to your motherboard's website for info on this.

2. No.

3. The sytem slows down, even on win2k.

With new processors, the L2 is programmed by the processor, not the motherboard, so the cacheable limit can be made indefinite depending on the processor.

Rags

EchoWars
1st June 2001, 00:00
Thanks Rags...unfortunately, Epox had nothing about it on their website. Perhaps I should look for technical documentation on VIA's website...

Technoid
1st June 2001, 13:11
God, I was so shure that the "X board/OS cant cashe/use more than X MB if X is X" topic had died by now!

BTW:

I have seen a lot os systems with more mem than the moderboard can cache and the were all faster than systems that haden't been uppgraded vith more memmory and even a lot of them that didn't have any cahce at all.

EchoWars
1st June 2001, 14:09
Hmmm...well, just a question that I thought some knowledgeable HW junkies might know. My K6-2+ system will be a mainstay of my home LAN for a game server and DVD player (HW decoded, of course...even the K6-2+ at 550MHz can't do software decoding very well) and because it is such a rare processor. Since it will be around awhile, thought I might pack it with all the memory that it can use. Seems, however, since it has only 512K of L2, that I am stuck with settling for 128Mb...

Greebe
1st June 2001, 15:31
You can add more, it just won't be cacheable. I have a S7 with AGP (Mtech Mustang R581a)that has 1 meg of L2 cache and it only caches 128meg.

Technoid
2nd June 2001, 02:14
Get all the memmory you can.

It's not like uncached memmory goes on half speed.

Rags
2nd June 2001, 02:39
If you exceed your cacheable memory, it WILL slow the system down, which is opposite of what you want.

Rags

cbman
2nd June 2001, 12:15
If uncached memory is still faster than HDD then I say more power to ya... if it isn't... then its not a very good idea http://forums.murc.ws/ubb/smile.gif

If you can borrow enough memory off people to check the performance in large memory allocation situations and if you notice no discenable difference with more than 128MB of ram then its not a worthwile upgrade. If however you notice that the performance has still increased then there should be nothing that stops you from getting it if its cheap enough.

IMCO (In my conceited opinion http://forums.murc.ws/ubb/biggrin.gif)

"Why stumble around saying its you humble opinion when you know it isn't..." http://forums.murc.ws/ubb/biggrin.gif

Charles

Rags
2nd June 2001, 13:30
Well, see the thing is that if you exceed the cacheable limit, what happens? Do you even have an inkling? When it gets allocated, it's cached ON THE HARD DRIVE! That's right folks. No benefit, actually a decreased benefit on average.

Rags

cbman
3rd June 2001, 16:04
You got me there Rags http://forums.murc.ws/ubb/smile.gif

I remembered that just after I posted but had to go to work so I couldn't change it

I think I had a hangover during that class http://forums.murc.ws/ubb/tongue.gif

EchoWars
4th June 2001, 14:15
Well I learned something...looks like 128Mb it is...