[QUOTE=Nelson;145011]My experience involves a Gigabyte p35 DS3 which would not OC well with a Q6600.[/QUOTE]My main home system is a Gigabyte GA-P35-DS3R with a Q6600, and it overclocks just fine. It'll get into Windows just fine at 3.6GHz, but for Prime95-stable I leave it at 3.4GHz in the winter (most of the time around here) or 3.2GHz in the brief period we can call summer.

[QUOTE=Nelson;145011][FONT=Arial]I cannot say whether a Q9550 95W will use sufficiently less power than a Q6600(B3) 105W my guess is there will not be a considerable difference. [/FONT][/QUOTE]Some of rev.B3 CPUs are known to overclock poorly or to produce a lot of heat. My advice: go for rev.G0 :tu:

A couple of you (James and db) who said the DS3 cools just fine even with over clocking ...my question is: Are you using any extra cooling hardware or extra fans or do you need to keep the case open ... etc?

[quote=James Heinrich;145022]My main home system is a Gigabyte GA-P35-DS3R with a Q6600, and it overclocks just fine. It'll get into Windows just fine at 3.6GHz, but for Prime95-stable I leave it at 3.4GHz in the winter (most of the time around here) or 3.2GHz in the brief period we can call summer.[/quote]

yeeah! now that you mention it the problem wasn't so much the CPU as it was the memory. With the Neo 2 I achieved 970Mhz with corsair XMS26400c4 with a multiplier of 1:1.25and 390 MHz fsb ~ 3.5 GHz. With the DS3R I couldn't get above 840 Mhz on the memory.

[quote=Cruelty;145027]Some of rev.B3 CPUs are known to overclock poorly or to produce a lot of heat. My advice: go for rev.G0 :tu:[/quote]

I like stars like to keep the cost down and a second hand Q6600 (B3) was enough cheaper that I took it. Actually I would rather have a 9450! Still I think your right because the darn thing doesn't want to complete a LLtest to my satisfaction. Even though I get no errors the residues still don't match. Very frustrating, because a stress test passes without a hitch for an excess of 48 hrs. Errors seem to occur at about 28M iterations enough for some Dbl Checks but no good when they start getting over 25M.

A P45 chipset doesn't give much more bang for the $1.

nelson

[QUOTE=Nelson;145032]yeeah! now that you mention it the problem wasn't so much the CPU as it was the memory. With the Neo 2 I achieved 970Mhz with corsair XMS26400c4 with a multiplier of 1:1.25and 390 MHz fsb ~ 3.5 GHz. With the DS3R I couldn't get above 840 Mhz on the memory.[/QUOTE]I can't push my RAM too far, unfortunately -- with 2 sticks in there works reasonably well, but with 4 sticks I can't get a decent stable overclock without pushing ram voltage up to ridiculous levels (e.g. 2.3V), so I've actually got my RAM underclocked to 756MHz right now (because the next set up pushes it to 908MHz, which it can't take with 4 sticks), which is FSB 378MHz * 2.0 (next multiplier is 2.4). When it gets really cold again I may be able to get stable back to 3.6GHz and the numbers all work out and I can be at 800MHz again.

[QUOTE=petrw1;145031]Are you using any extra cooling hardware or extra fans or do you need to keep the case open ... etc?[/QUOTE]I'm using the [url=http://www.scythe-usa.com/product/cpu/024/scinf1000.html]Scythe Infinity/Mugen CPU cooler[/url] in an [url=http://www.antec.com/usa/productDetails.php?lan=us&id=15900]Antec Nine Hundred case[/url], both fairly potent coolers.

[QUOTE=petrw1;145031]A couple of you (James and db) who said the DS3 cools just fine even with over clocking ...my question is: Are you using any extra cooling hardware or extra fans or do you need to keep the case open ... etc?[/QUOTE]

I'm using a Zalman 9700 with my P35-DS3 - great for cooling the CPU, but it's a "tower" type cooler. Not much down draft onto the motherboard. However, the PC does have a power supply with 120mm fan, and there's another 120mm fan at the rear. I suppose that compensates for the lack of downward draught from the Zalman.

[QUOTE=Nelson]My experience involves a Gigabyte p35 DS3 which would not OC well with a Q6600. Apparently the CPU power conversion on anything less than DS4 is not adequate to provide sufficient current to the CPU. [/QUOTE]

I've got my G0 rev Q6600 overclocked to 3.0GHz at stock voltage. It's been up (almost) 24/7 for the last 4 months crunching 4 instances of LL testing. To push it higher, I need to increase the voltage, which I'm not comfortable with for long term operation. However, when I first put the machine togther, I did run Prime stable for a day at 3.2GHz with 1.3V VCore.

The P35-DS4 might indeed have better power regulation since it uses an 8-pin ATX connector, while the DS3 uses a 4pin. However, this has changed in the P45 series. Both DS3 and DS4 use the 8-pin ATX connectors.