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TheManuel
06-06-2007, 11:08 PM
Greetings.

I recently built a budget PC with the following components:

Abit IB9 P965+ICH8
Core 2 Duo E4300
Wintec Ampo 2 X 1GB DDR2-5300

So far, I've had everything running at stock. When I put everything together, the memory defaulted to 200MHz rather than 266MHz so I left it alone for the time being. CPU-z is reading 2T for the command rate. I plan to start playing with overclocking now that I've had more time to dedicate to it. However, I have already noticed a couple of unexpected aspects of my system

First, I ran SiSoftware Sandra's Memory Bandwidth test and I am getting a dissapointing:
3550MB/s for Integer Buffered iSSE2
3544MB/s for Float Buffered iSSE2
Running at 200MHz, dual channel, the theoretica bandwidth is 6400MB/s so I was dissapointed to get a little more than half of this.
Is this bandwidth to be expected in real world for this system or are there some things I should be looking at?

The second issue I am having is that the CPU is showing 41 to 42ºC on the included Abit EQ motherboard monitoring application. My system temperature is showing 30ºC so my difference is ~12ºC. When I read the reviews for the processor in newegg, many people quoted temperatures of a few degrees over system temp with stock cooling. SpeedFan v 4.32 shows the CPUat the same temperature but shows Core 0 and Core 1 at ~26º which did not make much sense to me as I thought junction temperature was supposed to be higher than that of the cores.
Is my temperature normal or do I have a hotter than average CPU?

I am planning to do some mild overclocking (33% or so) but I've read elsewhere that it is not advisable to run Core 2 Duo's over 50ºC. If I am already at 42º and core temperature is anywhere near linearly proportional to clock speed, running the e4300 at 266MHz will easily push my CPU temperature over 50ºC, let alone push the overclocing even further.

I will appreciate your advice.

Manuel

ski
06-07-2007, 10:02 AM
Did you try setting the RAM speed at 266 MHz?
CPU temps in the low 40 C range is cool. A temperature differential of 12 C between the CPU and system is OK. My system's differential is approx. 18 C.
No comments on O/C. That's your call.

TheManuel
06-07-2007, 10:05 AM
I just realized that I quoted the wrong clock speed for my memory. It is actually DDR2-667 but it is currently running at 200MHz, not 333MHz.
The next step would be to start runnning faster but I still don't understand why I am getting such low bandwidth.
Per CPU-z, my memory latency is:
4-4-4-12

ski
06-07-2007, 11:40 AM
If the RAM's speed is automatically set by SPD in BIOS, then it may actually be DDR2-400. Did you try manually setting it to 333 MHz?

TheManuel
06-07-2007, 07:11 PM
I have not tried to set the speed up manually but I am confident it is DDR2-667. I bought it as such from newegg, the reviews are satifsactory and CPU-z reads the SPD information as PC2-5300.
I think the motherboard did that simply to match the FSB of the processor which is 800MHz.

ski
06-08-2007, 09:44 AM
Synchronizing the frequencies of the CPU and RAM is a good thing.
However, I'm wondering if the RAM can be manually set at 333 MHz.