Re: ram
On Fri, Apr 07, 2006 at 09:02:45AM -0400, Lennart Sorensen wrote:
> On Fri, Apr 07, 2006 at 06:57:06AM +0200, Francesco Pietra wrote:
> > In setting up a workstation with
> >
> > --two amd6a 265 opterons dual core
> > --Tyan K8WE S2895SA3NRF main board
> > --two 360GB raid1 hd (raid 1 software by debian)
> > --ram 2GB (Kingston KVR400D4R3A/2G - DDR 400 Ecc Registered), is any reason to
> > prefer two slots of memories 1GB each instead of a single 2GB slot?
> >
> > The technician here maintains that two slots are needed to have needed two
> > channels.
> >
> > Incidentally, the 2GB Kingston is charged in Italy six hundred euros, that is
> > more than twice the price in US. This is to recognize that we can circumvent
> > the market leader software houses (and be more efficient) but we cannot avoid
> > the system in our country which favors handlers against citizen (and against
> > scientific research activities). The results of such policy are under the
> > eyes.
>
> With 2 * 1GB, you get 6.4GB/s memory bandwidth. With 1 * 2GB, you get
> 3.2GB/s memory bandwidth. I think that is a reason to prefer the
> pair 1GB sticks
>
> Socket 939/940 AMD's have dual channel memory controllers to get double
> memory bandwidth, but only if you put in at least two sticks of memory
> (and into the right slots on the board).
Actually since you are using 2 cpus, you really would want at least 4
sticks of identical memory to get full performance from the system since
each cpu has a dual channel memory controller. You need need memory in
each channel of each cpu if you want the maximum performance.
Len Sorensen
Reply to:
- Follow-Ups:
- Re: ram
- From: Francesco Pietra <frapietra@alice.it>
- References:
- ram
- From: Francesco Pietra <frapietra@alice.it>
- Re: ram
- From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen)