Query about dual channel.

I don't think different Brand will be a problem if the RAM's timings and speed are same with the previous twos.

Please use transcend only as i have faced many problems with ram modules from different vendors on my previous Athlon Xp pc.Their architectures might conflict.

Thanks. Got the point.

as of now i've 2*1GB DDR2 667 ram.2day i brought another 2*1GB DDR@ 667 sticks.vista 32-bit detects only 2.94GB out of 4GB.if i remove 1 of the sticks even then Vista detects 2.94GB ram (dual channel config is maintained though).
my question is that if i add only one 1GB stick will inpact performance in a -ve way??

Yes I think so. Because the mems in dual channel mode will have double bandwidth whereas the single mem stick will have half the bandwidth (half the double i.e). So there wont be any symmetry among the data sent.

Choto_cheeta suggested something related to PAE(Physical Address Extension) that allows a maximum of 4GB of RAM to be detected in Win Vista/XP 32bit edition. Go *www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx
for more information.

Read *en.wikipedia.org/wiki/Physical_Address_Extension

It says::
PAE allows 32-bit Windows Server 2003 to access a full 4GB of memory.[clarify] However, Microsoft has pretty much abandoned PAE in the 32-bit versions of Windows XP SP2 and Windows Vista.[1] This is to avoid compatibility problems with the wide variety of third-party device drivers. For example, some incorrectly written drivers may cause problems when attempting DMA operations. [2] Thus, setting the PAE option to "ForceEnable" using the BCDEdit program likely has little effect in 32-bit Vista.

Click to expand...

Ask MVPs as they may help you in a better manner.

I have 2 512 MB DDR2 667 mhz ram on my M2NPV-VM in dual channel.
Now i want to buy a 1gb ram, will this combo work
512-1-512. ie two 512 mb sticks in dual and 1 gb in single mode

@cynosure
It has to work if u get another set of Kingston 2*1Gb sticks.
Coz In that way the first channel wud be 1Gb Transcent+1Gb Kinston and same is with the second channel.
Dual channel should work properly if both channels are identical in all manner.

Ive tested it on my mobo A8N E. I Used 512MB Transcent and 512 Mb Hynix at each channel and i got 2Gb in dual channel.
512 trans+512 hynix and another 512trans + 512 Hynix.

But to address 4G memory in vista, it requires a patch to be downloaded from MS site. So first install Vista on 2Gb and then dl the patch nd install. Restart. Turn off, then attach the another set of modules and its done.

But u should attach the modules in correct order.

@ cynosure. This shud be the order.
Transcent, Kingston, transcent , kingston.

@assasin
u can test the performance of memory using everest or Sisoft Sandra memory benchmarks. Do all the mem write, read, latency benchies and see which has got better performance. It dusnt depend on amount of memory, but only frequency, latency nd modes[single or dual ch].

Also point to be noted is:
Some mobos has problems with some modules or specific model of soem brands even if its a gud brand.

Always better to get single sided modules as most mobos has issues with dual sided modules of 1Gb nd greater.

@cynosure
If u plan to overclock, i wud suggest u get the transcent only as all modules cud easily work in da overclocked frequencies without problems. Otherwise some model of module can't go higher while the other set of modules can go higher, so the overclocking wud be limited.

@ruturaj3
No it won't work. Itll become 512+1G on first channel nd 512 on second. So by any way it wont work in dual channel.
To get it workin on dual channel, either uve to go for another 2x512 or 2x1G sticks in addition to ur current 2x512 sticks.

Thanks aravind. You replied what I was thinking was right!!