Why cant i run my DDR @ dual channel?

[bud888]

Hi all,

I recently upgraded the BIOS and installed a SATA HDD in my system (Gigabyte GA-8IPE1000 Pro MOBO) and afterwards my DDR memory (2*512MB PC3200) only runs at single channel, why?? how can i make it run on dual channel? I know my system supports it because it did before.

Both the modules are exactly the same spec etc. I trawled through the BIOS and couldnt find any options concerning this.

Can anyone offer any advice

Thanks in advance for any responses.

 

[tf1]

Ordinarily, it is only the presence of (virtually) identical memory in one of the memory buses that allows dual channel mode to work. (I say virtually because if you have slightly mis-matched memory - say one chip is CL2 and the other CL2.5 - the dual chammel mode will be enable but both memory chips would run at the slowest speed.)

Make sure that you have inserted the modules in the same channel and don't have one module in channel A and the other in Channel B: otherwise, the system will see and use the full memory but only run in single channel mode.

Regards: tf1

 

[cdogg]

In other words, make sure you have the modules in the same color connector.

See the photo and explanation here:

http://www.guru3d.com/article/mainboard/118/5/

As long as it worked before, you should have no trouble. You might want to reseat them if you continue to have problems.


~cdogg
[tab]"All paid jobs absorb and degrade the mind";
[tab][tab]- Aristotle
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[bud888]

Cheers for that. Altho still isnt working. I must have been imagining things cause i always had them plugged into slots 1 & 2 so it couldnt have worked before. I tried moving one of the dimms to slot 3 but still no luck.

I did notice something tho, altho my dimms have exactly the same manfacturer part number (crucial CT6464Z40B), one is double sided, the other single sided! Will that make a difference?? Everything else is identical, speed, parity, CL!!

Thanks again

 

[tf1]

The single-side/double-sided may just be the problem. Before committing to stating it definitely is the problem, I'd recommend seeing if you can borrow a pair of modules that definitely work in dual channel mode and make sure it isn't a mobo problem.

Though one final question (really stating the obvious) but you have got a P4 that supports dual channel?

Regards: tf1

 

[cdogg]

tf1,
I don't think the CPU needs to support it, does it? I thought it's solely based on the motherboard and type of modules you use.

bud888,
Call me crazy, but I have come across articles in the past that describe the same problem you're having. It turns out that single-sided and double-sided modules don't play well together. Sometimes they work, other times they don't. That could possibly be the issue here. I like tf1's suggestion to get your hands on a working set and try them in your system as a test.


~cdogg
[tab]"All paid jobs absorb and degrade the mind";
[tab][tab]- Aristotle
[tab][navy]For general rules and guidelines to get better answers, click here:[/navy] faq219-2884

 

[bud888]

Just checked my P4, it does support Dual Channel. Its a P4 2.4 Ghz 800FSB.

http://indigo.intel.com/compare_cpu/showchart.aspx?mmID=852348&familyID=1

It says in mobo manual that single/double sided should mix together BUT Kinsgton say that they dont. How are u supposed to add a matching dimm when the manfacturer codes dont differentiate between single/double sided. AHHHH!

I will see if i can lay my hands on some workings dimms, thanks guys.

 

[tf1]

Bud888

Yep, I think your correct. I'm confusing this with early P4/mobo combinations that only supported single channel PC 133 and a little later DDR 266 buses.

It is the mobo that provides the support for dual channel.

Regards: tf1