Q9550 won't post on DP45SG

I've been running a DP45SG (intel) mobo with a Q8600 with no probs. I wanted to use the virtualisation in Win 7 so got a Q9550. Popped it no - no post. Swapped back - no probs. Repeat - same result. Thought the Q9550 was DOA but the shop checked it out and it was fine. Intel chat support suggested a possible PSU issue (vague). I'm using a Thermaltake 550W - any thoughts?

i would say alteast a 650 watt PSU

Please go here to see if the board supports that processor with the minimum BIOS support: http://processormatch.intel.com/Co [...] ame=DP45SG

Bios is up to date - 0121, and the cpu is explicitly listed as being compatible with the mobo on the intel web site.

I haven't tried the CMOS reset yet. Since I put the old cpu back in - which works fine, just no virtualisation support... - couldn't I just go into the bios and restore default settings? I don't think I've done much to change them in any case. I haven't oc'ed this system or done anything unusual. Is the point that the bios will pick up different default settings with the new cpu? If that's the case, I definately see the point.

It's a situation where I have to pull everything apart and swap chips to try things and then put it all back together with the old cpu if it doesn't work. So I'm trying to get as many things to try as possible between sessions with the lid off. Those flimsy pins on the intel coolers weren't made to go on and off too many times...

anyway thanks to those responding so far. Any more ideas are most welcome.

I'll give it a try.

by the way - Valentino is a legend. Even though I'm an Aussie and have to back Stoner, I have huge respect for Rossi. It's going to be an interesting contest next year if they're both on top of their game.

Thanks to all for the advice so far, but unfortunately the problem persists.

I switched chips and removed the battery for about 1/2 hour. Unplugged the hdds and optical drives but left the video card in so that I could see if it started to post (no video on the board). Same result as before. Fans spin but no post - no signal to the monitor. Drop the old chip back in and all is sweet. The CMOS was reset because the clock was back to default.

So, I'm stumped - any other ideas?

Yeah, I did try it with the jumper in "configure" position but I think that only sends you into the bios interface once the post sequence begins. I haven't tried to boot into "recovery mode" (jumper off). Is there a reason to try that? Other than "what can it hurt?"...

Hmm. I'm still trying to get a response from Intel support. I'll do a bit more searching around for other things to try before pulling it all apart again - it's a bit of a pain because of the way the desk is situated. I might try regressing the bios a couple of versions. If it was supposed to be supported all the way back to 0073 and I'm on 0121, backing off to 0116 (or whatever) shouldn't hurt. Anyway thanks for the advice so far.

Hi Mahlon,

any luck with solving that problem? I have just (literally today) bought the same motherboard and cpu and after updating the bios to 0121 having used an older processor i still dont have any luck getting post on the q9550.

any help?

So. After trying all the things people on 3 forums suggested, all the things that intel email support and chat support suggested. I gave up and bought an Asus P5P43TD mb. It's pretty close to the DP45SG - P43 instead of P45 but uses the same I/O controller so windows doesn't get too confused. Sorry Intel, here's the bad news: I installed the Asus board with the Q9550 and it booted with no drama at all.

My windows 7 professional installation also started with no drama - I haven't yet tried logging into xp.

I'm using it now. Same memory, same PSU, same video card, same 3 hdds, same 2 optical drives. Problem solved. Since the DP45SG works fine with the Q8300, I left it in on the board and will probably use the board to build up an HTPC with spare parts sometime soon. Thanks to all who tried to help - I'm sure the advice was sound -just can't help dodgy engineering.