ok... I'm puzzeled.
Before I start let me give you some background...
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Specs:
MSI 648 MAX (6585) Motherboard
P4 2.4b ghz CPU (Vantec Aeroflow CPU HSF)
1 gig PC2700 Crucial (both with heat spreaders)
Turtle Beach Santa Cruz Sound Card
Albatron GeForce4 128 mb Video Card (Vantec VGA FAN)
60 gig Maxtor HD (enermax HD Rack)
56x cd rom
48x CDRW/16x DVD Combo
Firewire Card
WIN XP Pro OS
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Ok....
I've had this system for over 6 months and have had no problems until now.
As you can see above, I have 1 gig of Crucial pc2700 ram.
Well I decided and got another stick of 512 crucial pc2700.
I installed the stick, and hell broke loose... I started getting blue screens bla bla.... Thinking it was the stick of ram, I RMA'd it.
Got my second stick in the mail yesterday, installed it, and started getting the same blue screens...
(so it's not the stick)
Since I was overclocking, i thought that might be the prob, so I reset everything to normal. (no OC)
It worked fine for a short while, then i decided to OC a bit.
I noticed that when I didn't overclock (DRAM setting was set to "by SPD"), the DRAM timing would go to "2"
But when I OC'd, it would go to "2.5"
anyways, I OC'd the FSB like i had it before (139), and left the DRAM setting to "By fsb".
well, saved the settings to the bios, restared, and i got NO POST.
fine, this had happened to me before, I knew that all i had to do was restet the "CMO" or whatever that is called (the internal battery)
I did that, and it worked, it reset the settings, and I was able to get to the bios again.
Since i had that problem, i decided to leave all the setting standard with no OC, so that I would not have any problems.
Well, saved the settings, restarted, and it just WONT POST.
I took out the new stick of memory, and still same prob.
I am able to reste the motherboard, and it lets me get in the bios the first time, but then it just doesn't post.

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Sorry for this long post guys, but this is killing me.
I'm a web/graphic designer, and I depend on this computer.
If anybody can help me out that would be great, any suggestions are welcome.
Thanks for listening, thanks ahead of time.