C3's have better IMC for AM2 DDR2 speeds?

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RogueTrip

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I've read that the C3 revision of the 955/965 Phenom II's improved the DDR3 IMC and speeds. I haven't found anything talking about improved DDR2 IMC though.

Anyone replace a C2 on a AM2+ platform that was stuck at 800MHz DDR2 speeds when they had 1066MHz ram when filling all 4 slots and now able to use 1066MHz?!

I'm wondering because I wouldn't mind replacing my C2 940BE for this reason and also overclocking looks better ;). I'm stuck at 3.4GHz (1.4375v) currently using 8GB ram 1066MHz stuck at 800MHz. If not any better IMC, I guess I'll hold out and see if the 6 core cpu's will work on AM2+, lol!

On a side note, wonder whats up AMD's sleeve. I see a new bios release for my motherboard containing more CPU support. Yet nothing documented on which CPU's are supported yet. Hmmmmmm.

TIA!

EDIT: Ram is G.Skill DDR2 1066MHz (6-6-6-18). Stuck running at 800MHz (5-5-5-15), not really a big deal.....but since I paid for it......
Will run in pairs of 2x2GB at 1066MHz fine, just not 4x2GB.

Also new Bios is 1701 about the CPU updates.
 
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the quality of the DDR2 controllers hasn't changed in a long time. Even though it's not officially supported, it's a breeze to run 4 sticks. Just manually set the RAM speed to 1066(since it'll default at 800). I didn't even need to raise IMC voltage at all.
 
in his case it may be the motherboard hes using that doesnt supported 4 sticks of ddr2 1066.. cpu supports it no problem though.. even my pos 780g motherboard supports 4x1gb 1066 with my 940..
 
My Asus M3A78-T has had some people able to run 4 sticks at 1066, not everyone but again might be a CPU thing as I'm wondering.

My board is also a more sucky 4+1 power design vs. the M4A 8+2 design. I was just hoping someone had a answer though about the IMC on a C3.

You guys getting it to run @ 1066, what is your NB VID and NB Voltage, even if they are stock. Maybe mine is undervolted (1.175v NB VID/ 1.3v NB Voltage)? I know by default my 940 at stock bios overvolts the CPU at like 1.45v when spec is 1.325v needed. I really haven't messed with anything except multi and cpu voltage.
 
My stock NB VID was 1.10v and my NB was 1.20v. As I overclocked the Uncore(NB and L3cache), the NB VID is now running at 1.5v. I also raised the NB and HT to 1.28 to help stabilize everything.
 
Also depends on the memory; my OCZ's "low-voltage" 1066 absolutely will FAIL memtest86+ when four sticks are present, regardless of how much voltage bumps the system gets, but my GSkill's kits work great out-of-box at stock voltages.
 
I can run 4 2GB sticks with my original BE 940 when they first came out and a Foxcon 790GX/750 motherboard at 1066 and 5/5/5/12 timings.
 
Actually I could not do 4 sticks of ddr2-1066 at 1066mhz on my old 940be, but they run great at full speed and rating cas5 timings on my C2 955.

I def dont know c2 vs c3 but 940->955 was definitely an improvement.
 
C3 = Nigher NB and more Stable DDr2 clocking Vs C2....Even more so vs B3...

If i was getting a chip today C3 is the only one id get for DDR2 if you plan on pushing things. Especially with 4gigs of ram or all stots filled.
 
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