Processor Decision P8400 vs. T9400

Intel® P8400 45nm "Montevina" Core™2 Duo 2.26GHz w/3MB L2 On-die cache - 1066MHz FSB 25 watt - Blowout Special! (+65)

Intel® T9400 45nm "Montevina" Core™2 Duo 2.53GHz w/6MB L2 On-die cache - 1066MHz FSB 35 watt - Blowout Special!(+115)

I'm trying to decide between the two of these, some input would be really appreciated. Battery life and performance are both important, but I'm not sure how big of a difference there is in these two processors.

 

what apps will u run on that machine ?
if office work both of them will give you same performance
but the P series will give an additional 30minutes

 

In CPUmark the T9400 gets 1688 points and the P8400 gets 1533 points

http://www.cpubenchmark.net/cpu_list.php

 

Is there any proof to this statement other than anecdotal evidence? Just because the TDP figure shows a 10W difference doesnt necessarily mean the power consumption is going to follow a similar pattern. Also, most laptops dont spend their time running at max speed and usage at all times especially on battery even if we take into account the TDP difference. Take a look at the spec sheet for the T and P series processors, the TDP's rated at different power states are the same except for the max pstate where they differ.

 

I'm going to be using it for college....engineering major so stuff like CAD and MatLab

 

i would get the t9400 for sure

 

The P8400 will do what you want, but I would chose the T9400 for peace of mind. But in the end it depends on your buget.

 

The battery life difference between the two will be negligible. What is the base processor you are upgrading from?

 

T9400 for sure. 100%.

It is well worth the $50 difference...


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What are you using your CPU for? If you are using CPU intensive tasks, $50 for an upgrade is worth it. If you are doing CPU intensive tasks on the go, the P processor will give you better performance due to longer battery life. If you are just doing basic tasks, the cheaper P processor will suffice as you will not notice any speed difference in the faster T processor.

 

Delta Temps for the processor should be lower, saying this the computer will spend less energy for cooling.

Delta power usage actually will be lower, the power drained from a T processor will be higher than a P processor at the same status. Say the T is consuming 17W while the P processor is just using 12W.

So this is a noticeble difference, at least I saw that difference when I changed my T6400 with my P9500, I got more battery life, I measured with a real life test using clocks and intead of being based with the dumb vista battery manager.

 

If you really need the CPU power, I would suggest a higher-tier processor, such as the T9600. If you don't, it isn't worth the extra $50, what with the downsides that the T-series processor comes with.

 

The T9400 at idle will run cooler and should use not much more idle power mainly the only increase in idle power is from the extra cache. They both downclock to the same multiplier and then downlclock the bus (SuperLFM) to 800mhz at idle as well as share the same low 1600 Mhz power state.

At load is a different story but between the cache and speed if you have the money go for it. I went from a P7450 to a T9600 which is a bigger leap but no looking back, i dont even have the need to overclock anymore.

Undervolting can help negate the extra power needs.

 

I would probably go with the T9400.

Considering there are 25 watt 2.53 processors what intel is doing is binning the lower voltage processors to 25 wattt and those that do requre a higher voltage to 35 watts. If intel is setting all the t9400's to a higher fixed voltage then all of them will consume 35 watts. If it is just setting the voltage setting to what is required to make it work then 35 watts would be the worst case found in a specific t9400 unit. Even if it was the first case wherein intel is setting the same voltage for all t9400 there should be some headroom to undervolt depending on specific units.