E8400 underclocking on EP45-DS4 - Memory issues.

[-=Mr_B=-]

I've managed to get the system stable at 1.6Ghz (6x266) but when ever i try anything lower, the system flakes out. I THINK it's due to the memory not wanting to play ball. I'm running DDR2-8500, using a x4 multiplier for 1064 "MHz". (533 really, but thats how the BIOS reports it.) Simply due to this being the only thing that actually works. It's also the highest multi for the memory.

But, Gigabyte never did anything the easy way i guess, so they included options from 2-4, with A-D variants, with some oddities, 2.5 & 3.33 only available as some variants. Now, i cant seam to find a real manual anywhere, i only find the "install guide" @ Gigabytes site, and my own seams to have gone missing. Anyone know where to got the info?

The memory has SPD info for 266-533, 400 should be what i need for 1.2GHz (6x200) with a x4 memory multi, to net me 800MHz reported as memory buss speed, and PC-2-6400, but yet, this doesn't seam to work. I also have a pair of PC2-4200, that should be a lower watt component, but with those installed the system isn't booting at all, i'm guessing it's trying to hard, wanting to boot at a higher frequency.

If it's not instantly obvious, I'm trying to turn this in to a low watt system for near idle 24/7 usage. The system cant be made "to slow" for the workload, meaning there is no limits to the creativity. So far i've gone from 125w to 88w at full load, but only 77w to 72w when near idle. I'd have to say, it's not turning out quite as i was hoping. I am going to replace the stupid 9600GT for a 5450 and lose near 15 watt across the board, and that will pretty much be the most effective measure of the lot. (The 9600GT was never intended to be a part of this build, but the PCI-cards that were seam to have passed away. Neglect, perhaps. A 5450 512MB DDR3 is supposedly about 5-6.5w, with the DDR3 versions being lower then DDR2 versions. The 9600GT is supposedly 22w or so. I found this link a useful resource. First time i found it i looked it over, and closed it. Took me hours to find it again the next time i thought about it, and "needed it". *sigh*)

Any insight, hints, or ideas?
B!

 

[-=Mr_B=-]

Slight update. Someone loaned me a pair of PC2-6400 sticks, and what do you know. 240x3.33 for a 800 speed on memory, and it booted straight up. Also allowed me to drop the vCore to 0.8v, (according to CPU-Z 0.768v) and the meeter now slowly shifts back and fourth between 71-72w for idle, and 81-82w for full load. At 1.44GHz it's less then half as fast as it used to be as well. If i can lose another 15-16w with a GFX change, then i'm in the right ballpark.
Drastic performance cuts to get (just barely) a 10% power-saving feature. I'll have to try and remember that this system needs a different motherboard if someone walks in to my apartment with a good motherboard with (a lot) less stuff on then this one has.

I still have yet to start trying to drop voltages on the memories, but since i for what ever reason cant seam to figure out what setting does what, it seams unlikely to net me that much. Also, i'm not sure, but watt savings on memory shouldn't be that great to start with? Just shy of 2w idle, and 2.5w's or something full load? Each stick, that is. Even a good tweak then is likely to save me what. 1w in total? I'll try it, who knows, perhaps i can figure out what makes me belly-flop when i try to go lower on the CPU, ideally i would like to hit something like 6x200 on the CPU, and something like 2x200 for the memory. (1.2GHz, possibly even a slight tweak to vCore again, and my OCZ PC2-8500 would be running at less then half speed. Possibly gaining me some room to drop the vMem... Wishfull thinking for the win?)
B!

 

[-=Mr_B=-]

Strange. The BIOS has a feature for saving alternate BIOS settings to slots for easy access & recall. But something about it isn't quite right. Or, something about the system doesn't quite add up.

If i reset the CMOS, i can quick and easy enter the BIOS, and key in my values.
266MHz x6, 1.6GHz, check. Lock PCI-E to 100MHz, check. Set memory to x3, 800MHz, check. vCore, 0.8v Check. Cool. Save, and exit. Boots. No questions asked.
Will run Prime95 at least over night, no problems.

In the search for lower values, such as 220MHz, i keep messing something up, and not really keeping good enough track of what works, or not, so when it craps out on me, i have to start over. Now would be a good time to use the settings i saved before, right?
Wrong. If i load that 1.6GHz config above, it wont boot. If i load it, and then put the vCore at 0.825v, it will boot. But i cant put it back to 0.8v just yet. I have to let Windows boot, shutdown, and then it will let me set it to 0.8v, and it boots. I'd be willing to accept that as "Ok, the CPU wont do cold boot from 0.8v, if it wasn't for the fact that the system will do just that. Power it off, after having it set to 0.8v, working, and pull the plug on it, just as a good measure, and 20 mins later (I was eating) put the plug back, and power it on, and it works. This **** is crazy. At least i found a workaround, i simply saved both profiles to my CMOS, and boot to windows with the0.825v one, and then shutdown and do over. But it's insane. No idea what's going on really.
B!

 

[-=Mr_B=-]

At this point i'm booting at 1200MHz, memory at 533 @ 5-5-5-15, 1.5v. Not really expecting huge gains from this point on, but, for good measure i guess i should try and find the "bottom" of the scale when it comes to voltage on the memory. However, running hours on end of memtest86+ to confirm if it's ok or not is getting boring, fast. The memory in question is "Infineon Siemens" according to memtest86+, reads hys72t128020hu3.7a on the sticker, PC2-4200. 1.8v, 4-4-4-11. I relaxed the timings as a means to be able to drop vMem a bit, but at this point... I didn't expect it to be stable at 1.5v to be honest. Does anyone have prior experience with how low memory "like this" is "usually" able to go? "Like this" and "usually" since... well, it's note really a common situation.
B!