More RAM = less performance?

[spastim]

Hi all

I've just put another 512MB DDR 333mhz Ram in my machine, and now i benchmark lower in aquamark 3.

My system spec is:

MSI KT400 mobo (need to find out the exact model i guess)
1GB DDR 333mhz RAM
Athlon 3000XP CPU
120/80GB WD 8mb cache HD's
ATI X800XT PE GPU

before when i had half the RAM in it i got over 45,000 in aquamark 3. Now with 1GB i get just under 40,000.
The Ram is in slots 1 and 2. The new RAM is higher quality than the old RAM?
If only i had the mobo manual still. I can't find anything on the MSI website about it as the products on there all sound different to my mobo. Maybe mines been discontinued?
Help someone please! Even tho my system will run half life 2 fine, Doom 3 is smooth as anything on max, and any game out this year will have no problems, i need more performance!
I do make my own music ( www.owfk.co.uk ) on my PC and this slowdown is affecting cubase too!

Thanx in advance!

[Chaffers]

Welcome to TechIMO!

Just to make sure that it is the RAM, how about just having the old stick in there, running benchmarks, and then having only the new stick and running benchmarks...

which OS are you running?

[draboo]

speculation only:

i believe you should put the ram in slots no.1 and no. 3 to get duel channel ddr working.

after you change slots,look at the bios diagnosis screen upon bootup. it should tell you whether its "duel channel enabled" . should tell you how much ram is installed ,too..

are both sticks of ram match?

also,you can go to start and right click on My Computer then Properties. that screen should tell you how much ram there is installed .

[RedFury]

Might have something to do with Ram timings too. I'm not nearly as well versed on the various settings and how they affect performance as I should, but I do know that having that much RAM in a system it is better to have matched pairs, and you will find some that recommend having ECC instead of the usual Non ECC RAM with a gig or better.

[spastim]

Cheers guys, i'll try your ideas tonight and let u know how i fared.

[Peter M]

The board might have had to step back in RAM timings. The more chips you add to a RAM bus, the more parasitic capacitance is messing with the bus signals - and thus the more relaxed must the timing become.

It might even have stepped back a notch in RAM frequency. DDR400 is specified for one single DIMM, DDR333 for two, three-DIMM setups are for DDR266. Some mainboards push those specified limits a bit, but there's little complaining if they adhere to the specifications.