How much RAM can a motherboard effectively manage

BillyBob313

Junior Member
Oct 31, 2004
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I am in the market for a new motherboard and have been burned twice in the past when it comes to a boards ability to manage RAM.

My first board was supposed to handle 128MB but after purchasing the RAM I found out it could only handle 64MB due to a chipset limitation. My second motherboard was supposed to handle 512MB of RAM but slows down with anything more than 256MB. I have been told but Crucial that this is due to the size (1MB) of the motherboards cache.

I see lots of new motherboards advertized with huge RAM capacities in the GB+ range but still with only 1Mb of onboard cache.

Needless to say I am more confused than ever. Can anyone shed some light on this. I'm getting tired of wasting my money on RAM modules I cannot use.

Thanks
 

NTB

Diamond Member
Mar 26, 2001
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Originally posted by: BillyBob313
I am in the market for a new motherboard and have been burned twice in the past when it comes to a boards ability to manage RAM.

meaning what? too many sticks would make it unstable? it wouldn't recognize all the ram you put in?

The board I just bought (for an AMD64 socket-754 chip) tops out at 2GB; the first socket can hold up to 1 GB and the other two can hold up to 512MB a piece, as long as the sticks are single-sided. If the second stick you want to use it double sided, then only 2 sockets can be used, if I remember correctly. A third one won't work. Intel I don't know - haven't messed with them much.

Nate
 

NTB

Diamond Member
Mar 26, 2001
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Originally posted by: BillyBob313
The motherboard slows down when I put in a second 256MB stick.

It is a FIC VA 503+ motherboard.

Mine does that too; not sure why. The memory speed drops from DDR400 to DDR 333 when you add a second stick. I haven't seen any noticeable hit in performance though. Then again, I don't play many games, either.

Nate
 

The J

Senior member
Aug 30, 2004
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I have a Shuttle AK38/N with a VIA KT333CF chipset and recently found that it is unable to handle 1GB of RAM without constantly crashing in my games. 512MB and 768MB seem to work fine, but not 1GB. I don't know if that's due to the motherboard or chipset, though.
 

mauiblue

Senior member
Aug 8, 2004
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I've got a Soyo P4I875P Dragon 2 v1.0 Black Label and that can take a max of 4GB of RAM. But my understanding is that if OCing, 512 GB is the max you should have. I didn't want to take the extra RAM out because I do a lot of video editing and digital photos. So I tried my hand at OCing with that much of RAM. The result is that I OC'ed the CPU from 3.2 MHz to 3.58 MHz (FSB frequency set at 224 MHz and vCore at 1.6 which is the max in the BIOS). Not bad:).

All the best and Happy Halloween!
 

BillyBob313

Junior Member
Oct 31, 2004
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My data transfer rate drops oorm just over 1000MBits/sec to 400MBits/sec when I add the second stick. The performance drop is very noticeable.

There must be more than the onboard cache size which affects RAM performance otherwise none of the new motherboards with 1MB L2 cache would support more than 256MB of RAM either.
 

klah

Diamond Member
Aug 13, 2002
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Originally posted by: BillyBob313

It is a FIC VA 503+ motherboard.

My data transfer rate drops oorm just over 1000MBits/sec to 400MBits/sec when I add the second stick. The performance drop is very noticeable.

There must be more than the onboard cache size which affects RAM performance otherwise none of the new motherboards with 1MB L2 cache would support more than 256MB of RAM either.

L2 cache was moved from the motherboard to the cpu-die about 6 years ago. I doubt you are going to get much help here with that motherboard since it was released 7 years ago.

 

osage

Diamond Member
Jul 16, 2000
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ASRock K8S8X mobo with the SIS755 chipset, works flawlessly with 2x1Gb sticks of PC3200. No memory speed slowdowns, no data transfer rate issues at all.

I would buy another one if they still make them, I can't understand why the stopped production on this board.
 

BillyBob313

Junior Member
Oct 31, 2004
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I am actually in the market for a new motherboard and do not want to repeat the expierence with the last two. From what I can tell even some of the new motherboards lose perfromance if you try an run the maximum RAM stated by the manufacturer.

My expierence has been that the maximum RAM a motherboard can physically hold/recognize is different than how much it can use without taking a performance hit.

Even though my FIC VA-503+ is older I am using an AMD K6-2+ processor with on die L2 which relegates the 1Mb onboard cache to L3. The performance hit is the same whether I use a processor with on-die L2 cache or onboard L2.