945PM memory @ 533Mhz + dual channel

Hello,

I have 2 questions about memory compatibility of the Intel 945PM chip, but I can't think of a better title to put. I hope people don't mind my not so informative title.

1st.
According to this Intel page, 945PM takes 4GB of RAM @ 533Mhz.
Does that mean if I put 4GB of RAM in the board, it will only run at 533MHz instead of 677?

2nd.
That page also says the chip supports dual-channel, so if I put in 2 paired-sticks of RAM in my T60, I will have effective memory speed to be 1066Mhz? Now I wonder how big the difference is between 533Mhz and 1066Mhz RAM speed.

1 more.
I think I recall having seen some mention about T60 supports SATA300, but that Intel page only lists SATA150 for the 945pm chip. What's the deal here?

Thank you in advance.

 

SATA 300 is most likely the speed supported by the hard disk, however, the actual speed that the Intel 945 chipset can suppot, is SATA 150. Don't worry about performance, because there will be no difference between the two. Thats because the hard disk cannot transfer at a rate of 150 MB/s in the first place. Even with a 7200 RPM hard disk, the rate is around 70 to 80 MB/s.

Dual channel doesn't double the frequency. It allows a higher bandwidth, from 64-bit from single channel to 128-bit with dual channel. On paper, the idea sounds good. In real life however, the increase in performance is only around 5%, in memory intensive applications. So, its best normally to ignore dual channel.

 

For SATA300 vs SATA150, I am not surprised if there is no gain in performance due to bottlenecks, but for memory channel, I would imagine that gives a huge boost in performance just like RAID-0 vs JBOD.
Are you sure about the performance gain is only about 5%?

 

And dont forget, most recent Intel chipset supports Intel Flex Technology, that is, supporting dual channel in different size of memory bank. So if you have 512MB preinstalled and want to add 1GB in the remaining slot, the chipset will activate the dual channel regardless the difference between the slot.

 

I have linked some benchmarks below, that should give you an insight into the small performance gain. The first one isn't the best, as it is tested on an older machine, however, it shwos the rend well, like the second link.

http://www.hardcoreware.net/reviews/review-169-3.htm
http://laptoplogic.com/resources/detail.php?id=20&page=3

sapibobo brings up a good point, in that the Intel 945 chipset can support asynchronous dual channel, when using modules with unequal densities. Agan, there will be little to no performance increase, but it will function in almost dual channel fashion.

 

Including 945pm?

 

Thank you very much, I bow to you!
I won't eye on any dual-channel/parity cr@p on 945pm anymore.

 

Yes. There are some advantages dual memory give rather than single memory channel. One of them is decreasing the bottleneck between CPU and RAM. Please refer to this article from wikipedia :
http://en.wikipedia.org/wiki/Dual-channel

Testing from devhardware.com clearly shows advantages dual channel gives above single channel. Note that the biggest gain happened in synthetic benchmark.
http://www.devhardware.com/c/a/Memory/Dual-Channel/2/

While the results aren’t breath taking, they do offer improvement for nothing. In terms of real-world application throughput, actual gains are highly dependent on your individual workload. Basic business programs like Word and Excel won't suddenly surge ahead on a dual-channel platform, but toss in some high-end image editing, demanding 3D games, and heavy multitasking, and the benefits become clear. It's all about bandwidth -- and it's why innovations such as dual-channel memory controllers, Hyper-Threading, and faster system buses have joined raw CPU speeds in the PC performance spotlight.
http://www.cpuplanet.com/features/article.php/30231_1587771_1