Guden Oden said:Steve,
I don't think there's a single Opteron mobo planned, much less actually RELEASED, that does not have separate DIMMs for each CPU. You know why? Because it would be plain dumb.
Perhaps Tyan counts as dumb, too?
First and foremost, the cost saving would be minimal at best. The Opteron chips themselves already account for a major part of the system cost, the mobo a minor one, and the cash saved on leaving out memory sockets for one CPU even less.
Let alone form factors, topology, trace layouts, etc... It's called pricing-to-market (PTM)...
Second, you'd lose a lot of the benefit of having two CPUs to begin with, resulting in a lot of wasted money rather than saved when both CPUs get starved of data. You'd have an on-die memory controller sitting there doing NOTHING, which means a lack of several gigabytes per second of useable bandwidth as well as halved maximum memory capacity!
As already stated - not unless you have a NUMA aware OS under heavy memory bandwidth situations. The beauty of Opteron PTP is the collateral gain in aggregate bandwidth from both local & remote memory.
Third, performance hit would be considerable. It's not smart to save money where it results in the biggest possible performance hit in a system, especially if it means the smallest possible cost saving.
Switching from SCSI harddrives to 10k RPM SATA might be a worthy cost saving for a rendering box or small server, but skimping on a few plastic DIMMs? Jesus!
Yep, that magic acronym again - PTM.
Yeah, sure... Obviously not as many as you, though...Got any more bright ideas while you're at it?