Will this memory combo work?

[paidbyhalf13]

I recently bought more memory for my PC to take advantage of the max for my mobo (8GB) so i tried my best through amazon to buy another matching set. TWIN2X4096-6400C4DHX 4GB pack

After installing it froze on bios and after restarting it would load bios...so I read in details the actual model number and it turns out they are off by 1.
my system has C4DHX
New memory C5DHX this small detail was in the lower part of the page or i would of noticed. it says 1.8v for C5D while my current C4D takes 2.1v

I am going to turn them back in for a full refund unless i can actually use them. So my experiment. Can i drop my current volts to 1.8v then install the new memory will that work? here's the rest of my current specs. Or will i have to manually make timings one notch higher? or something else...

Asus P5N32-E SLI 680i nForce (most recent BIOS)
Intel Core 2 Duo E7500 2.93GHZ Overclocked to 3.85GHZ
260 GTX SLI - OC'd
PSU Corsair AX850
TWIN2X4096-6400C4DHX
Windows 7 Ultimate 64 bit

EDIt: so just saw default timing comparisons between C4D and C5D

C4D = 4-4-4-12 @ 2.1V

C5D = 5-5-5-18 @ 1.8V

Will it be impossible to put these on the same Mobo? any configuration idea would help a lot. Thanks

 

[COLGeek]

Are your BIOS settings manually set or set to AUTO (or default) settings now? If not already set to AUTO, try that to allow the mobo to configure automatically. If you are already there, you can try the lowered setting, it won't harm anything. Good luck!

 

[paidbyhalf13]

Are your BIOS settings manually set or set to AUTO (or default) settings now? If not already set to AUTO, try that to allow the mobo to configure automatically. If you are already there, you can try the lowered setting, it won't harm anything. Good luck!

Thanks, I had to disable "SLI-memory" and put memory volts to Auto. The timings are set to auto and all are synced as 5-5-5-18 and mem volts are supposedly 2.1v on auto atm. Not sure if those readings are accurate. Also I am curious, through cpu-z it says JEDEC #1, JEDEC #2, AND EPP#1 for my C4D models and only jedec 1,2 for C5D. What do these represent?

Another question. I just ran sisoft's memory bandwidth testing and have 6GB/s all around with a 94.44% bandwidth efficiency was wondering if these numbers are good. Thanks again for your reply

 

[paidbyhalf13]

Best answer selected by paidbyhalf13.

 

[COLGeek]

Thanks, I had to disable "SLI-memory" and put memory volts to Auto. The timings are set to auto and all are synced as 5-5-5-18 and mem volts are supposedly 2.1v on auto atm. Not sure if those readings are accurate. Also I am curious, through cpu-z it says JEDEC #1, JEDEC #2, AND EPP#1 for my C4D models and only jedec 1,2 for C5D. What do these represent?

Another question. I just ran sisoft's memory bandwidth testing and have 6GB/s all around with a 94.44% bandwidth efficiency was wondering if these numbers are good. Thanks again for your reply

JEDEC and EPP refer to memory standards and protocols and CPU-Z is just informing you of what the modules support. If you want to make your head hurt, go here for more:

http://www.jedec.org/

Your efficiency numbers look fine. If you are stable now, you should be good to go.

Good luck!

 

[paidbyhalf13]

JEDEC and EPP refer to memory standards and protocols and CPU-Z is just informing you of what the modules support. If you want to make your head hurt, go here for more:

http://www.jedec.org/

Your efficiency numbers look fine. If you are stable now, you should be good to go.

Good luck!

Turns out having 2 sets of memory that need 2 different memory voltages is a bad idea for my motherboard and/or chipset. After a couple hours the memory went out and i could never get it past bios even after resetting the cmos. So back to 4gb for now lol. I'll probably look for another 4 gig kit with 2.1v settings. lesson learn

 

[COLGeek]

Turns out having 2 sets of memory that need 2 different memory voltages is a bad idea for my motherboard and/or chipset. After a couple hours the memory went out and i could never get it past bios even after resetting the cmos. So back to 4gb for now lol. I'll probably look for another 4 gig kit with 2.1v settings. lesson learn

Understood. It has happened to all of us in some shape or form. Since you just bought one pair, just match those and sell your old ones (or keep for backup, just in case.....).