dual core/ram question

[wasamonkey]

fallin behind on tech
and can't find anything on the dual cores regarding ram access

well first, can both cores run off of one stick (as dual channel is becoming common, i'm guessing this may be the required configuration)

second, if i do have to run 2 sticks, do both cores have access to the ram or does each have access to half the total ram

thanks in advance

 

[sithscout80]

Both cores have access to the entire RAM. You can use single (1 stick) or dual channel (2 sticks) RAM, it doesn't matter.
The memory controller deals with all these issues.

 

[The_OGS]

Hi wasamonkey,
In a modern system with dual-channel memory, you could always configure it in single-channel - say you had mismatched sticks or only 1 memory stick, no problem.
Now, DDR2 memory running at 266MHz (533DDR) as an example, has a bandwidth of 4200MB/second, that's why they call it PC2-4200.
In dual-channel mode, the 64-bit memory will present 128-bit bandwidth to the system. The total theoretical memory bandwidth will therefore become 8400MB/s.
All CPU cores have full highspeed access to all the memory. AMD CPUs contain an integrated memory controller, which works very well (and allows their motherboards a slight price advantage).
Intel CPUs still have their memory controller on the motherboard, but have recently speeded up access to it. Intel also uses a setup now where both CPU cores can share a single large fullspeed cache, which helps make their architecture fast too.
Modern DDR2 mobos actually claim to be somewhat more tolerant of mis-matched memory configurations than before, and will attempt to run dual-channel in ways that previously would fail. So that's a good thing, LoL, if it works...
Regards

 

[evilr00t]

You would be better off buying two sticks of 512 KB (for 1 Gig) than buying 1 stick of 1 Gig RAM.

Even if you want to play the 'RAM price waiting game'?

<-- same boat, new rig:
Core 2 Duo E6300 $182.50
Asus P5B Deluxe $194.99
Kingston HyperX KHX6000D2/1G 1GB DDR2-750 $111.00
^ used to be a 2GB kit for $160, but that's just not the case now.

Total: $488.49 Budget: $500
Stuff lying around:
Video: 3dfx Voodoo4 4500 32M PCI (Yeah... the GMA X3000 is better)
HDD: Atlas 15K II 73GB SCSI HDD
PSU: FSP 420W PSU

 

[evilr00t]

Could you do me a favor and test the performance difference between single channel and dual channel DDR2?
We all know that C2D doesn't suffer too much from increased memory latency. It would be interesting to see the effect of memory *bandwidth* on the performance of C2D.

 

[wasamonkey]

Thanks guys, this is definately the best place i've ever found for hardware related info

cheers

 

[enforcer22]

DDR memory doubles it's data rate by 'interleaving' the data within memory. So you will always get double the bandwidth/access performance by pairing up your ram sticks. It defeats the purpose of the the first D in DDR to run a single stick of RAM. You would be better off buying two sticks of 512 KB (for 1 Gig) than buying 1 stick of 1 Gig RAM.

Thats not really true it will get DDR with a single stick simply becuase DDR double data rate is how it sends information Dual channel is the ammount of channels it has to send on (its more like quad pumping in a simplistic way of putting it.) it sends twice the data in either mode just in dual channle mode it has two "pipes" to send double the data on.