AMD Athlon II X4 640 OC Question

Hi guys first post so Hi!

Anywho for XMAS I received my new custom rig (will post specs below). I've been running my stock clock rate and cooler ever since and haven't touched one bit of OC'ing in my life Recently i have been thinking of OC'in my AMD Athlon II 640 CPU to roughly 3.4/3.6GHz so i get some increase from 3GHz.

What I want to know is some starting pointers because i am a beginner in OC'ing. I understand basic risks like CPU damage and board damage plus know that i defo need an upgrade from stock cooler. I've ordered a Corsair A70 as it fit my budget and looked pretty decent.

Cheers,
Lone

Oh Yes, My Specs :

Motherboard: AsRock N68C-S UCC Edition
CPU: AMD Athlon II X4 640 3GHz
GFX Card: Sapphire HD Radeon 5670 1GB GDDR5
Memory: 4GB (2x2GB Sticks) DDR3 1666MHz (Corsair XMS3 2GB and One Unknown Stick 2GB)
OS: Windows 7 Ultimate x64-Bit
PSU: 700W PSU with 42 amp running on seperate +12v Rails (+12v1=21a. +12v2=21a)

Please download and install:

CPU-z

HWMonitor

Prime95

Please remove the Corsair memory stick temporarily and then . . .

Please run CPU-z and upload pics of these three tabs: "CPU", "Memory" and "SPD". These tabs will tell us a lot about your hardware and your bios settings. Particularly, we need to know more about that "unknown" memory stick and this may help with that.

What CPU cooler are you using? Stock, OEM?

As said in my first post I am running a stock cooler but I don't think it's an AMD one as there is no AMD Sticker in the middle of the fan.

Here are the Screenshots you've requested:

CPU:



Memory:



SPD - Slot #1:



SPD - Slot #2:

Looking at the JEDEC tables in the bottom two pics it looks like your "No name" memory stick is actually a Micron brand (or has Micron chips anyway) and is actually rated higher than the Corsair stick, 1522 mhz vs. 1333 mhz, respectively. If you're wondering where I got that, the JEDEC tables read information that has actually been encoded on the modules by the manufacturer at the factory. CPU-z displays the memory bus speed for the ram which is half the rated data transfer speed for DDRx ram. So multiply by two to get the actual data transfer speed. Because the two sticks are not the same brand, speed and timings, the motherboard has lowered the ram speed to DDR3 800 in order to allow you to run in dual channel mode. This is significantly below what either of your ram sticks are capable of. Proper dual channel memory consists of a matched pair from the factory. Your performance is taking a significant hit from this.

The likely limiting factor in your overclocking if your are using an OEM-type heatsink is high core temperatures. My first pointer is, With everything on stock settings, check core temps with a freeware program called HWMonitor while stressing the CPU with another freeware program called Prime95. With HWMonitor open on the desktop, run the Prime95 blend test for 15 minutes and then upload pics of the HWMonitor interface. This will give us an idea of how much overclocking headroom you have from a core temp standpoint. We know that AMD CPUs begin to get unstable when overclocking when the core temps begin to exceed mid 50s C.

Ok cheers, as said i've ordered a Corsair A70 Cooler so i guess the OEM cooler is irrelevant. Here is a HWMonitor on my STOCK Cooler if it's relevant for now:

This doesn't tell us much as it looks like these temps are at idle instead of under full load, like Prime95 for 15 minutes. But as you say, it is irrelevant since you have an A70 on the way.

I think your ram being two so different sticks will prove to be a big problem in your overclocking. I hope the new cooler fits. It will require a case of at least 8" wide measured from outside panel to outside panel in order to clear the side panel.

Ok I hope that my Cooler will come tomorrow as I misread the delievry and it said 5-7 days instead of 2-3 so hopefully tomorrow. I have a standard/large ATX Case and my Motherboard is Micro-ATX 9if it makes a difference. If it doesnt fit with the side on i'll leave it off but i think it'll fit. Will get back to you tomorrow maybe next week as i'm on holiday on saturday till sunday the week after just so you know. Do you think I will achieve 3.4/3.6 on Stock Voltage? or Even reach that far?

Well, you said in your opening post you have already gotten it to "3.4-3.6" on the stock cooler. But did you actually put it under a real stress test to confirm stability at the level of overclock? Buy stress testing to confirm stability around here we mean passing 2 hours or more of Prime95 blend.

If I were you, I'd consider selling those two ram sticks on ebay and buying a matched pair.

I wonder how much that am2 630a chipset would hold back the A4-640.

I know the ht link is ht 1.0, (half rate nothing you can do about that), but hopefully you can up the nb-cpu multi to get the it upto 2.0-2.4ghz and get a bit more memory throughput.

I'd be a little worried about the power phase it's pretty poor, but provided voltages aren't increased too much you might be able to get the cpu upto 3.4-3.5 nb-cpu 2000-2400.

As Trents has said you need a matching pair of ram modules. Personally I would have aimed for something like an Amd 760g or 770 if the budget was tight.

Yeah, I have concerns about the AM2 chipset as well. The big problem there is the fact that the HT Link and the CPUNB probably cannot be isolated from one another and if you drive up the NB, the HT Link goes with it and becomes the source of instability. Actually, there are several limiting factors in this system as far as overclocking goes. If Lone Wolf is going to upgrade the motherboard he might as well go for socket AM3 as he needs to get new ram anyway. The CPU is a pretty stout AM3 processor so he's good to go there.

The CPU is an AM3 CPU, I won't be upgrading my Motherboard as I don't have the money to do that plus it was a gift from my Parents... Also in my first post I stated "Recently i have been thinking of OC'in my AMD Athlon II 640 CPU to roughly 3.4/3.6GHz so i get some increase from 3GHz. " not that I had got it to 3.4/3.6 on stock cooler...