You type: > We have quite a bit of room to overclock now: >
That maybe so with somewhat lower temps. Only the doing of the overclock will show how much is really doable.
Your Signatue says > AMD Athlon II x250 Regor [3Ghz Dual Core OC to 3.3] >
So you have 'already' been overclocking and you should already know how to get that 300Mhz overclock. So DO it and let us see the captures of that speed as outlined below.
This is the what and how we need to see the captures since you will be FSB clocking which raises more than just the CPU speed, but the ram speed, the NB Speed and CPU/NB speed et al. You can post a capture of P95 running blend mode if you like but do not let it over-run or cover any of those other 4 captures we need fully visible.
These are the types of information that most users supply in order to be able to help them very much. Of course beginning with a setting that is 'known' to pass P95 Blend mode makes good sense, because a failed P95 Blend test is not going to give a baseline of a configuration that 'does' work.
CPU Tab in CPUz from CPUID com
Memory Tab in CPUz from CPUID com
SPD Tab in CPUz from CPUID com
And this is screen capture of HWMonitor (free version) from CPUID com
HWMonitor has been scrolled enough and large enough to show Min/Max of Voltages and includes the CPU CORE TEMPS fully visible.
This capture is made of HWMonitor after it has been open on the desktop logging Min/Max temps and voltages while Prime 95 was running Blend Mode test on all cores for at least 20 mins and then the capture of HWMonitor was made and it shows the Min/Max temps and voltages before P95 Blend was started and while running P95 Blend mode and gives much greater insight into how the system is performing without guessing.
In order to attach screenshots of images as suggested, first crop and capture the images with Snipping Tool found in Windows Accessories or equivalent. Then click on Go Advanced, a button at the bottom of every new post window. Then click on the little paperclip tool at the top of the Advanced post window when it opens. Clicking on the paperclip tool brings up the file browser/upload tool and the rest is fairly obvious.