wierd memory problem

[Paul]

I upgraded my memory last week, a stick of PC 3200 1Gb 400Mhz ram, and in
Bios recognized at CPU clock speed as 400.

Today I got another stick exactly the same and installed it, the BIOS
recognized it but the clock speed has dropped to 333Mhz and in Vista the
performance has dropped from 4.3 to 4.1 !

Can anyone advise please?

Paul

 

[Michael]

Paul,

You don't say how many banks of memory you are using, however in general
they are not in pairs then you will take a performance hit.
1 bank slow
2 banks fast
3 banks slow
4 banks fast.

This is not true of all memory configurations, you will have to consult your
manual for actual requirements/limits.

Michael

 

[Paul]

Sorry, it was 1 bank of 1GB, now I have added a 2nd bank of another Gb.

 

[Michael]

Paul,
It is still possible that it is a 'pairing' problem.
On my dell there are 4 slots
Slot 1 and slot 3 are of one color, slot 2 and slot 4 are another color.

I could put 1GB in slot 1 and 2 and supposedly it would work but slower.
I actually have 1 GB in slot 1 and 1GB in slot 3, slot 2,4 are empty.

It would make sense to put in consecutive slots but that is not always
correct. If your connectors are different colors your setup my be like mine.

Michael
Vista Home Premium, Dell XPS410, 2GB

 

[eRipper]

Hi Paul,

Memory upgrades should be done in consideration of CPU type.
Hyperthreading, dual core, and core 2 duo CPU's should be done in MATCHED
pairs (dual channel) and in same color banks as another poster mentioned to
get the best performance. MATCHED pairs would consist of same ram
manufacturer, lot numbers and chips used on sticks. Easiest way to get
matched pairs is to get a "kit". A 1gb kit would actually be 2/512mb sticks.
See link below.

http://www.newegg.com/Product/Produ...ktop+Memory)-_-Kingston+Technology-_-20141423

 

[Peter Lawton]

There's also a quite well known issue with the memory controllers on socket
939 AMD processors, in that they can run 4 sticks of single sided memory or
two sticks of double sided memory at 400MHz, but can only run 4 sticks of
double sided memory at 333MHz.

The CPU has 2 memory controllers, each controller connects to 2 RAM slots
and dual sided memory has 2 banks per DIMM. 2 double sided DIMMs make 4
banks and the memory controllers can't cope with 4 banks each at 400MHz

Unfortunately getting single sided 1Gb sticks is almost impossible, it's
hard enough to get single sided 512Mb sticks.

Usually single sided DIMMs only have chips on one side and dual sided DIMMs
have chips on both sides, but this isn't true 100% of the time.

Peter Lawton