CPU upgrade issue (Aspire 8943G)

I have an Aspire 8943G, and I've recently decided to upgrade the processor from the stock i5 450M up to the i7 720QM. All logic dictates this should work.

However, today, I swapped in the new CPU only to find I my laptop was shutting itself off immediately. The exact process was: Press the button, brief moment of power, the heatsink fan JUST gets a lick of power (enough to judder, not even begin to rotate), and then the laptop shuts itself down. This was an unchanging cycle. I checked all the connections, reseated the CPU (much to my irritation), and still nothing. I've stuck my old CPU back in and am curious as to why this isn't working...?

Anyone got any ideas?
I'm in the process up updating the BIOS to 1.06 at the moment, in the vague hope that will get it to work.

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staticwolf

UPDATE: Now running BIOS 1.06. Is it likely the 720QM will work this time around? Or am I still missing something?

julian_R

The I5 is a 35 watt CPU

http://ark.intel.com/products/49022/Intel-Core-i5-450M-Processor-3M-cache-2_40-GHz

and the I7 is a 45 watt CPU

http://ark.intel.com/products/43122/Intel-Core-i7-720QM-Processor-6M-Cache-1_60-GHz

So it might be a power option in the bios?

But I think because the 720Q does not have an IGP you have to go into bios and manually select to only use the discrete graphics?

I assume you used thermo past on the new cpu also?

staticwolf

As I said, I assumed the fact I disconnected all the other hardware would mean that the Mobo was able to supply the i7 with enough power. I did use thermal paste.

I did not, however, switch to discrete, for one very good reason. I have no idea why, but my BIOS gives me the option for "switchable" and "discrete", but not for "integrated". What makes this more perculiar is that "switchable" only seems to use the ATI chip, whereas "discrete" only uses the integrated graphics.