RAM Mystery...

[koocha]

Hey

I've got 1Gb High Density PC3200 and 2 x 256Mb Low Density PC3700 in my system.

1024 + 256 + 256 = 1536Mb, yes?

No.

When I've got my 1Gb high density stick in, it ignores the rest. It doesn't matter which slot it's in - it's not fussy. So the total my computer ever shows is 1gb.

Is this because high density ram can't work with low density ram? If I got another high density stick would it work ok together?

I've got an Epox 8KRA2+ witha Via KT600 chipset on it.

Thanks for your help

Tim

[LeChris]

It should 'eat' any combinations of different modules. In BIOS, set the parameters manually instead of 'by SPD'/automatic. As for DDR400, it may only supports up to two sticks. So you may try DDR333/166MHz first.

I also noticed that the parameter 'interleaving' in BIOS can have effect on RAM recognition/stability if differently sized sticks are installed.

If you get your 1.5gigs to work, i recommend to check them with Memtest, esp. with DDR400: http://www.memtest.org/

[koocha]

Apparently my board does only support 2 sticks running at DDR400 (officially), but it doesn't work with 2 in either.

I'll have a look in my BIOS in a bit.

Thanks

Tim

[koocha]

SUCCESS!

I dropped the speed down from 400 to 333mhz and it detects it all.

BUT, now the question is...

Am I better running 1.5Gb at 333Mhz or 1Gb at 400Mhz?

[blueball]

Depends what you are doing I'm afraid. If you are playing BF2 or editing large pictures then the extra 512Mb will help more than the faster speed. Otherwise go with 1 gb @ 400 as its faster for most things just not once you start paging to disk.

[LeChris]

Sounds like a restriction from the BIOS: if it detects more than 2 banks(your 1GB stick has 2, the 256MB 1 each stick), only two are picked for operation in DDR400. I guess this is intended to prevent a user from using more modules than supported by the chipset at DDR400. But you should also try some timings manually, eg increasing the CAS/CL-value to 3 - maybe the timing values in the SPD from the 1GB are to aggressive for your old 256er.

Since your are running a 200MHz FSB, DDR400 has some little performance advantages over DDR333 - we're talking about maybe 3..4%. 1GB should be enough for most tasks - except when you're experiencing heavy HDD-usage while having one or more demanding program running at the same time.

[koocha]

I usually run quite a lot (inc battlefield 2 and photoshop - but not at the same time!). I'll see how I get on with 1.5Gb