New AMD system build, show me the OC! :)

[Kuzi]

CPU: Phenom II X4 965 BE C3 125W
Motherboard: MSI 790FX-GD70
RAM: Corsair Dominator GT CMG4GX3M2B1600C7 8GB (4x2GB) (7-7-7-20)
Pioneer BDR-205 Blue-ray 12X BD-R 16X DVD+R Burner
SSD : OCZ Vertex 2 (not available yet)
HD : Western Digital WD1001FALS Caviar Black 1TB
Video: XFX Radeon HD 5870
PSU: Corsair CMPSU-750HX 750W

I know 8GB memory may affect my OC to a certain degree, but these have BEMP profile for AMD systems, and the IMC in C3 CPUs supposedly has better support when using 4 DIMMS. I haven't decided on a CPU cooler yet, maybe the Corsair H50. Although I don't mind getting something air based if it's better and not too huge/noisy

The OCZ SandForce SSDs are not out yet, so I won't order this system until they are released. Hopefully it happens within the next month, otherwise I'll just get an Intel X25M G2.

Any and all suggestions are welcome, thanks.

 

[Martimus]

That is nearly the same system I was thinking of getting. How much is that costing you? (I'm asking because some of your components are better than what I was planning, so if it is an acceptable total cost I will just switch to what you have planned.)

 

[SlowSpyder]

For whatever it's worth, adding 4GB to get a total of 8GB didn't affect my OC at all. But then again I'm not pushing this chip to it's absolute limit. It gets very finicky around 3.8GHz, I'm not sure if the memory would affect the chip if it's pushed really far. But for my moderate OC the memory was not a factor.

The easy way is to just bump the multiplier, but you're leaving performanec on the table if you don't push the HT/NB speed. I see a lot of NB's at ~2.8GHz. As the cores speed up they need the NB/L3 to keep up, so be sure to tinker with that. Again, I barely pushed my NB/L3 but the chip is fast enough for me now. Maybe I'll push it some more in the future. At any rate, be sure to play with the NB/L3 speeds as you'll see in benches that it does affect the chip.

My chip is happy at 1.5 volts, my temps are tolerable, but I'm not going for every last MHz. I think most people don't like to got that high, the 1.4x range is where most people keep thes chips. But, just watch your temps and have fun.

 

[Kuzi]

That is nearly the same system I was thinking of getting. How much is that costing you? (I'm asking because some of your components are better than what I was planning, so if it is an acceptable total cost I will just switch to what you have planned.)

Without the SSD and the Blue-ray writer it comes to about $1500. I'm assuming the OCZ Vertex 2 would cost ~$500 for the smaller version (100GB?). And I still need a CPU cooler so that would get the cost to over $2k.

One thing I should mention is that those Dominator sticks cost over $200 for 4GB, so the 8GB RAM alone is costing $400. You can easily find better deals than that, especially for RAM with looser timings. For my case I want to try and get the RAM to run at 6-6-6-20 timings @ 1333Mhz which seems very doable with those sticks

 

[Kuzi]

For whatever it's worth, adding 4GB to get a total of 8GB didn't affect my OC at all. But then again I'm not pushing this chip to it's absolute limit. It gets very finicky around 3.8GHz, I'm not sure if the memory would affect the chip if it's pushed really far. But for my moderate OC the memory was not a factor.

The easy way is to just bump the multiplier, but you're leaving performanec on the table if you don't push the HT/NB speed. I see a lot of NB's at ~2.8GHz. As the cores speed up they need the NB/L3 to keep up, so be sure to tinker with that. Again, I barely pushed my NB/L3 but the chip is fast enough for me now. Maybe I'll push it some more in the future. At any rate, be sure to play with the NB/L3 speeds as you'll see in benches that it does affect the chip.

My chip is happy at 1.5 volts, my temps are tolerable, but I'm not going for every last MHz. I think most people don't like to got that high, the 1.4x range is where most people keep thes chips. But, just watch your temps and have fun.

Thanks SlowSpyder. You know I'm hoping I can get it to 4GHz stable, but if not even 3.8GHz will be good enough for me

I was checking a PII overclocking thread at XS some time back and it showed that the NB at 2.6GHz is perfect for 3.8 to 4GHz CPU. So that's what I will try to go for most likely.

 

[SlowSpyder]

Thanks SlowSpyder. You know I'm hoping I can get it to 4GHz stable, but if not even 3.8GHz will be good enough for me

I was checking a PII overclocking thread at XS some time back and it showed that the NB at 2.6GHz is perfect for 3.8 to 4GHz CPU. So that's what I will try to go for most likely.

Those numbers (3.8GHz/2.6GHz) will most likely be acheivable I'd think. From what I understand 4GHz is iffy, you may get it, may not. These chips seem to hit a wall around there. Good luck!

 

[konakona]

for AM3, I heard the norm is 2.6-2.8 range for NB, is there any truth to it?
Mine wasn't quite stable doing 3.0@1.5v. so I backed it down to 2.8 and now its completely stable with lower voltage. the core is at 3.9. Not to shabby for C2 I guess.

 

[BD231]

Anything over 2400 on the northbridge of a C2 can cause potential problems I've found, C3's I've not played with just yet. Oddly the biggest factor in getting the northbridge to 2.6ghz is actually your motherboard's mosfet configuration. Some motherboards simply won't allow you to get much past 2.4ghz stable, and some fair even worse.

In your case 2.4ghz won't be a problem, I'm running that right now on an x3 720 without issue in a MSI c-45, an el-cheapo motherboard in contrast to that GD70.

 

[Kuzi]

The other issue is that 4 memory DIMMS put more stress on the NB so it may be harder to OC. But it's really a few % performance difference between say 2.2GHz and 2.6GHz.

Btw anyone tried the Corsair Hydro H50 cooler? I read some good reviews about it.