Need Advice on Bad RAM slots

[LausDeo86]

I have the GA-P35-DS3L motherboard. I am using 2 2GB sticks of G.skill memory (F2-8500CL5D-4GBPK)

I have recently completed a thorough testing of my motherboard’s RAM slots using Memtest86+
I plan on overclocking my PC, and prior to actually starting, I discovered I had a bad RAM DIMM which is being RMA’d right now. My other RAM DIMM is okay. So I decided to use this DIMM to test the memory slots of my motherboard to make sure they are good as I have heard that motherboard RAM slots can be faulty sometimes.

Well, it turns out that two out of the four RAM slots of my motherboard are bad, and to make matters worse, each one is on a different dual channel memory configuration! That is, it is impossible for me to do dual channel memory now because one DIMM for each dual channel setup is faulty!

This is how I did testing. The good RAM DIMM passed Memtest86+ on the two good RAM slots after 7 hours+ testing and 17+ passes with no errors. On the bad RAM DIMM slots, I would get errors, and one in particular I would get 100’s of errors within the first minute of testing, and I tried that test 3 times with the same results.

I don’t think RMAing my mobo is possible since Gigabyte has a ridiculous 2-3 week rma return period and I need to use my PC in the meantime.

So my question is: How bad would it be to run my RAM DIMMS in non-dual channel configuration (remember: I’m wanting to overclock my PC so I want speed of course)? Also, is the cons of non-dual channel bad enough that I should consider buying a new mobo? Lastly, I doubt it, but can I force the two new DIMM slots to be dual channel somehow?

Thanks ahead of time for your help and advice.

 

[Mongox]

I gotta say, I don't think it's possible to test all 4 RAM slots with a single module. There's no reason to believe that one stick will operate in your slots DDRII2 or DDRII4. And slot DDRII3 could be iffy with a single module. Always use slot 1 for one module and slots 1 & 3 for two modules. Only use slots 2 & 4 if the others won't work.

And if one of your existing modules was bad, your testing of the slots with 2 modules is invalid.

If you run your RAM as single channel, they become 533MHz DRAM instead of 1066. So basically, half the speed with no advantages like lower CLs.

Which slots are bad?

 

[badge]

Also, read the MB manual. Under RAM installation in the manual what Mongox is saying is laid out in black and white there.

 

[LausDeo86]

I gotta say, I don't think it's possible to test all 4 RAM slots with a single module. There's no reason to believe that one stick will operate in your slots DDRII2 or DDRII4. And slot DDRII3 could be iffy with a single module. Always use slot 1 for one module and slots 1 & 3 for two modules. Only use slots 2 & 4 if the others won't work.

And if one of your existing modules was bad, your testing of the slots with 2 modules is invalid.

If you run your RAM as single channel, they become 533MHz DRAM instead of 1066. So basically, half the speed with no advantages like lower CLs.

Which slots are bad?

Why couldn't you test the four slots with a single module? You can run a test with one RAM DIMM in a single slot per test. If you take a single module, put it in slot 1, test it, and it passes, then put it in slot 2 and test that, and it passes, then put it in slot 3 and it fails, then put it is slot 4 and it fails, then you can conclude slots 1 and 2 are good and 3 and 4 are bad. I asked G.skill on the phone if testing with one module is accurate and he said yes. But maybe I'm wrong?

Well, when I tested two DIMMS together I got errors (I tested them in the DDII2 and DDRII4 slots), so that's when I decided to start testing the DIMMS individually (one at a time). I tested both DIMMS individually on the DDRII2 slot and one DIMM passed and one failed. Based on that, I RMA'd the failed DIMM. (Hopefully that test was accurate but G.SKill will determine if that DIMM was in fact defective). As far as the rest of the testing, I used the "good" DIMM that passed in the DDRII2 slot. Using this DIMM by itself, I tested all 4 DDRII slots, and the results were: DDRII1 and DDRII2 passed with flying colors. DDRII3 failed miserable (within minutes) and DDRII4 also failed.

So I take it from you that it is possible my DDRII3 and DDRII4 slots might not actually be bad since my test using one module may be innacurate for those slots, but instead I need to test using two RAM modules to get accurate results. I understand that I should first test DDRII1 and DDRII3 once I get my other DIMM back and I have two DIMMS again and it might actually pass, despite the fact DDRII3 failed miserably with just one DIMM. Is that correct?

Thank you for your help and I'll await your reply.

 

[LausDeo86]

Also, read the MB manual. Under RAM installation in the manual what Mongox is saying is laid out in black and white there.

My mobo manual says absolutely nothing about about what order to put your DIMMS in. Regarding the use of 2 RAM DIMMS, all it says is if you want dual channell with two DIMMS, use DDRII1 and DDII3 or DDRII2 and DDRII4 slots. I am aware of that and that's what I did when I tested them together.

It says nothing else about what to do if you have 1 module, nor does it say any priority like "use these slots first, and then if those don't work, move on to these slots"

 

[Mongox]

Yes, slot 3 and 4 were NEVER designed to hold a single module. They are only for the 2nd module of a dual channel pair. That's why they failed - and that's good news, since they shouldn't have worked!

Slots 1 or 2 can be used to test a single module - and should be used for that.

The preferred placement of 2 modules is in slots 1 and 3. Only use 2 & 4 if needed, for example, to avoid a cpu cooler.

Sounds like your motherboard is fine and you only need to wait for the 2nd module.

 

[Mongox]

My mobo manual says absolutely nothing about about what order to put your DIMMS in. Regarding the use of 2 RAM DIMMS, all it says is if you want dual channell with two DIMMS, use DDRII1 and DDII3 or DDRII2 and DDRII4 slots. I am aware of that and that's what I did when I tested them together.

It says nothing else about what to do if you have 1 module, nor does it say any priority like "use these slots first, and then if those don't work, move on to these slots"

It's kinda assumed that you'd put 1 module into the slot named slot 1.

And I did see something there about using 1 & 3 unless otherwise needed.

 

[badge]

Sounds like your motherboard is fine and you only need to wait for the 2nd module.

I'd say so.

 

[LausDeo86]

Yes, slot 3 and 4 were NEVER designed to hold a single module. They are only for the 2nd module of a dual channel pair. That's why they failed - and that's good news, since they shouldn't have worked!

Slots 1 or 2 can be used to test a single module - and should be used for that.

The preferred placement of 2 modules is in slots 1 and 3. Only use 2 & 4 if needed, for example, to avoid a cpu cooler.

Sounds like your motherboard is fine and you only need to wait for the 2nd module.

Thank you very much for your help. I am greatly relieved and am glad to learn more about how memory works and the optimal placement of memory. I will test it with 2 modules when the other one comes. Since I have installed the rather large Mugen 2 CPU cooler, I may want to install the DIMMS in DDRII2 and DDRII4 so that the DDRII2 RAM isn't as much under the fan of the Mugen 2 cooler and so has more space for better heat dissipation.

 

[LausDeo86]

Sounds like your motherboard is fine and you only need to wait for the 2nd module.

I'd say so.

Thank you for your opinion and help.

 

[badge]

Welcome. Always use the DIMM slot nearest to the CPU (DIMM slot 1) to test individual DIMMs of RAM. If the system shows problems with the other slots populated, be sure to go into BIOS and set the RAM voltage, speed and timings to Mfg. specifications. Otherwise the system BIOS defaults the RAM to JEDEC standards which may not provide enough voltage for multiple DIMMS.