Asrock AM2NF4G-SATA Overclocking fun

[yyrkoon]

Well, where to start . . . its been a long time since I've overclocked a system (last OC I've had sucsess with was on an Intel P55 233mmx system, YEARS ago), and thought since I've already considered buying a new motherboard, and CPU, why 9the hell not try now. Since the current motherboard, and CPU I own (listed in my signature) is of the budget variety, I wasnt expecting huge results, yet I was shooting for the best possible OC I could achieve, while the system remained stable. Anyhow, down to buisness.

BIOS settings: 225 CPU Frequency, 12x CPU Multiplier

Here, I played around with with the DDR2, and Northbridge<->Southbridge settings, and no matter what I did, rasing the CPU Frequency any higher, resulted in the system un-able to enter into the WinXP desktop. nTune reported the folowing values:

Reference clock(HTT): 224.106mhz
HT Multiplier: 5.0x
HT bus frequency: 1120.528mhz
CPU Multiplier: 12x
CPU core frequency: 2689.268mhz
Memory clock: 800.000(DDR)mhz
Memory bus speed: 896.432(DDR2)mhz

Sandra synthetic benchmark results:

CPU arithmetic: Drytone ALU 9746MIPS
Whetstone iSSE3 8246MFLOPS

CPU Multimedia: Integer x4 aEMMX/aSSE 25308 it/s
Floating-Point x4 iSSE 27467 it/s

Memory bandwidth: Int Buff'd iSSE2 7260MB/s
Float Buff'd iSSE2 7242MB/s

Memory latency: 87ns
speed factor 77.8

Cache and memory: Combined index 9284MB/s
speed factor 7.5

BIOS settings: 250 CPU Frequency, 11x CPU Multiplier, Memory @ DDR2-667, NB<->SB 800mhz

Reference clock(HTT): 249.009mhz
HT Multiplier: 4.0x
HT bus frequency: 996.037mhz
CPU Multiplier: 11x
CPU core frequency: 2739.103mhz
Memory clock: 666(DDR)mhz
Memory bus speed: 829.201(DDR2)mhz

Sandra synthetic benchmark results:

CPU arithmetic: Drytone ALU 9933MIPS
Whetstone iSSE3 8404MFLOPS

CPU Multimedia: Integer x4 aEMMX/aSSE 25756 it/s
Floating-Point x4 iSSE 27991 it/s

Memory bandwidth: Int Buff'd iSSE2 7141MB/s
Float Buff'd iSSE2 7072MB/s

Memory latency: 89ns
speed factor 81.1

Cache and memory: Combined index 9053MB/s
speed factor 8.2

I'll leave out the stock scores, just because it should be obvious these two overclocks should be faster, and it'll make this post a bit shorter.

Well, there you have it, a 16% OC, without being able to adjust the vcore upwards, on a budget system. Now since it has been awhile since I've OC'd a system, I may have missed something (besides the obvious game benchmarks . . . maybe I'll add Oblivion scores at some later point), but if anyone would like to comment, please feel free to do so, I'm all ears.

 

[JarredWalton]

The lack of Vcore adjustments is a major problem with ASRock motherboards, and that is almost certainly limiting your overclock. Also, the lack of higher memory voltages is also going to limit your overclock. When used the setting of 12 x 225 and had the memory running at DDR2-900 (I guess technically it was 12 x 224 and memory running at DDR2-896), the maximum memory voltage of 1.95V was almost certainly the limiting factor. If you drop the memory ratio down to DDR2-667 (CPU/8), I'm sure you could push the CPU to about the same clock speed.

My experience with overclocking AMD K8 processors is that they almost always require a bit more voltage than stock as you start pushing the overclock beyond 200-300 MHz. There may be exceptions to this rule, and better cooling might help out as well, but without Vcore adjustments you are very unlikely to overclock more than ~300 MHz with complete stability.

As for your benchmarks, I would pitch Sandra from testing. It is a purely theoretical benchmark, and if you noticed the basically only use it to look at memory bandwidth, and even then the correlation between real-world benchmarks and Sandra scores is questionable. I think probably the best quick and easy benchmark of true CPU + memory performance is to run some video encoding tests. AutoGK along with DivX or XviD should show the effects of both memory bandwidth as well as CPU clock speed. Realistically, however, you will almost always be bottleneck by either CPU speed or your graphics card. The difference between top-of-the-line memory and mediocre memory usually isn't more than 5% without getting into extreme overclocking.

The other point I would like to make is that without better cooling I really don't think you can get much higher than 2800 MHz on a 3800+ single core processor. There's a reason AMD topped out at 2.8 GHz after all. 3000 MHz is reasonable with better cooling, but I doubt it's worth the additional cost. Hope that helps.

Jarred Walton
Editor
AnandTech.com

 

[yyrkoon]

Thanks for the reply Jarred. I did want to mention that while running Prime95 + SuperPI 32M, at the same time, the core temperature never went above 124F (according to nvmonitor), do you still think heat would be an issue here ? As for AMDs '2.8GHZ barrier', I always thought that was simular to Intels GHZ barrier, and was largely attrubited to circut cross-talk. Granted I've always known about heat issues, but 124F when ambient temperature is 80f+ (100F+ outside), I never even blinked at that temperature. At idle, the CPU is around 106F, and even cooler as ambient temperature goes down. Right now, I'm using the stock heatsink / fan combo, with artic silver 5, mainly because my heatsink options are limited, as I'm using a Lian Li PC-G50 case, which is a reverse ATX layout, with PSU on the bottom, and sideways (right above the CPU). I love this case though, very compact, and very good for wire managment.

Currently, I'm still having problems getting this board to run stable. It randomly locks up still, so for now, I've set everything to stock, and put the memory into BIOS compatability mode. Only problem with this, is that my CPU is CPU/12, and memory is 400mhzDDR (even with stock setttings manually set in the BIOS). Anyhow if this doesnt fix my problem, the next on my list of checking is to disable the onboard ethernet, and putting an Intel card in either a PCIE slot, or PCI slot(we have some Intel management fast ethernet cards lying around here), or I may buy an Intel GbE card. Again, this problem occurs reguardless if I'm Overclocking, and doesnt seem to have anything to do with running a load, or not (matter of a fact, it almost nearly happens when I'm away from, and not using the PC, but last time it happened while running SuperPI+Prime95 simotaneously). This is why I still havent been able to trace the problem. If you have any thoughts here, they would be greatly appriciated, but I'm running out of options. Would be a terrible shame if this problem was un-resolvable, without changing out the motherboard (to a new brand).

[EDIT]

Oh, another thing I'd like to add, that I'm unsure of, is that everytime I reboot, the nv program that runs for the graphics pops up a notification baloon , telling me that SLI has been disabled etc. Now since I'm using a eVGA 7600GT, and the motherboard has onboard NV44 graphics, I cant help but wonder if the onboard graphics is TRUELY disabled or not. In the BIOS, I have Graphics mode set to PCIE, and shared memory for the onboard graphics set to auto, but as far as I'm aware, there isnt more I can do to disable the onboard graphics.

 

[yyrkoon]

So, today, this motherboard finally ran for more than 3 days stright without crashing. What I did was go into the BIOS, manually set memory voltage to 'Ultra high', disbaled my serial, and paralel ports, and turned CPU. SATA, and memory spread spectrum off (disabled). If I had to guess which was the problem, I'd have to draw a straw between the memory voltages (even though I've had it manualy set here before . .), or some sort of IRQ sharing conflict, which should be resolved by disabling the serial, and paralel ports.

Anyhow, I'm back to 11x mult, 250 CPU, as I could not get the CPU frequency any higher than 230 mhz, and that required me to set the memory in DDR2-533. Now I'm just torn between getting a ABIT AN9 32x (non fata1ity) for futher OC'n , or a ABIT AB9 pro, with a E6300-E6600 CPU, and ditch AMD for awhile . . .