Why did Lenovo use T9xx0 processors in the T400?

I have a T400 on the way, and the one thing I'm slightly disappointed with is that it's got a T9400. I don't understand why they used the Intel T-series processors at all when they all have P-series listed in the parts page. A P9500 would've given the same performance- 2.53 ghz, 1066 mhz, 6mb cache- all while consuming 10W less.

Will there be a noticeable difference in battery life compared to a P-series processor?

What is Idle States that P8xx0 processors have?

 

I'll have to check idle states(if you tell me how) when my T400(P8400) and X200(P8600) get back from repairs. I'll have to redo some research, but I'm just about certain I've seen someone post up that they swapped in a P9700 into a T400 and it worked just fine. It was an upgrade I've been considering.

 

when the t400 first came out, there were only p8xx0 processors and t9xx0 processors. And also, when the p9xx0 processors came out they were still more expensive than their t9xx0 counterparts.

 

This is true... looking on Fleabay a little while ago seems to indicate that the P9700 goes for about the same price as the T9900 does... around $450USD or so.

I did a little digging and found this thread which seems to confirm that the P9700 will work in a T400 without any BIOS modding or any other issues: http://forum.notebookreview.com/lenovo-ibm/398705-p9700-t400.html

 

P9700 was a factory cpu. It should work fine.

I definitely will leave the T9400 in. Looks like a $200+ upgrade to go to a P9500 which is the equivalent.

I'd also void the 2yrs left on my warranty.

 

Definitely the $$$. Unless you originally got a super slow (and cheap) T-series chip, I find no reason to upgrade to go with the 10W diff.

 

The T9400 in my W500 performs gives about the same battery time as my T500 with the P8700 CPU when both are used on integrated graphics card mode. A LED LCD would give you far more battery time difference than a P9xxx versus T9xxx.

The T9400 CPU is actually quite efficient in terms of power use and thermal management. Under most condition you would not notice a marginal increase in battery time. In my opinion, don't waste the money.

The difference would show itself if you constantly run the laptop with full cpu usage, which for most people is quite rare.

 

I don't plan on changing it for the plethora of reasons discussed here. You're right that 10W is only at full load.

How much more power efficient is the led display? My T400 will have the 300nit LG screen so I don't expect to have it at more than 60-70% brightness in most situations.

 

it gives about 5 to 8% battery power time difference at full brightness on a 15.4 inch machine.

 

Okay... this kinda leads into a related question. I'll be interested in upgrading my T400's CPU down the road, so... P9700, or T9900? 2.8GhZ vs 3.06GhZ, same cache, and 10W TDP difference? Which would be the better choice, given both are going to be about the same as far as cost? I'm pumping up from a P8400, so in my case I think the upgrade could very well be worth it.

 

Just my personal opinion here, but for most people it's not worth the money or effort, unless you've got a specific need to run the CPU at full capacity frequently.

 

At today's prices, why not get an X9100. These Extreme series CPUs sell for under $300 on ebay and can be reliably overclocked to 3.6 GHz to 3.8 GHz. ThrottleStop lets you unlock the multiplier on these CPUs so no bios support is needed as long as it boots up which it should.

http://forum.notebookreview.com/har...unlock-core-2-extreme-multiplier-windows.html

If a P series and a T series CPU are adjusted to the same MHz and core voltage, you'll be hard pressed finding any difference in power consumption at idle or full load. The TDP is just a rating and becomes meaningless once you start manually adjusting the core voltage.

 

Hm... some interesting points to consider. I may wind up doing some moderate video editing as learning how to do some 3D modeling and CAD work on the T400 as time goes on... just stuff I've always wanted to learn how to do. I'm kinda on the fence with all that right now and will definitely be testing some programs out to see how well they do with the P8400 before I decide to throw that much into a CPU upgrade. I just like to do a lot of homework before I commit to buy.

 

You could sell your P8400 or P8600 on ebay for $100 to $150. The net cost for a 60% increase in CPU performance wouldn't be too bad at all.

 

Don't overclock your CPU, the speed gain is not worth the trouble.

Also, CAD and 3D modelling are more GPU intensive. So unless you have a good grade workstation GPU, then there is no point in upgrading the CPU for the sake of 3D modelling.

 

Wont the X9100 put you up 10W of heat from the T series processors ? Can the T400 heatsink handle the extra heat at full load (stock speeds even?)

 

What trouble. Get an X9100 CPU, unlock the multiplier and set it to whatever speed you want. That doesn't sound like too much trouble for a 50% to 60% increase in CPU performance. That can make a big difference in a lot of applications. Here's what one user had to say about this feature.

The TDP rating of a CPU has nothing to do with the actual power consumption. That is mostly determined by the core voltage you are using and the MHz you are running at. If you equalize those two variables then power consumption will be close to identical between a T and P series CPU.

If you start overclocking and increasing the MHz and core voltage then yes, that will consume a lot more power and create more heat. That's the good thing about ThrottleStop. It's easy to create a different profile for AC or battery use and you can switch between the two profiles automatically. You can save overclocking for when you are on AC power and working at a desk and when you switch to battery power, it will run at its default speed or whatever speed you choose.

 

1. has people successfully unlocked the multiplier on a thinkpad to overclock the cpu?

2. the CPU performance increase of 50% to 60% is obtained in what condition? under idealised benchmark condition?

3. If you are going to quote, at least quote the correct user statement. Is a quad core (q9100) comparable to the dual core cpu (x9100)? Also which system is the person you are quoting from using? a 14.1 inch laptop, 15.4 inch laptop or a 17 inch laptop?

4. TDP rating is the maximum power consumption of the CPU under full CPU load.

5. More heat in a T400 is not a good thing, since you will strain the fan and making it run at full speed all the time. Also the problem of more heat doesn't go away if you are on AC power or battery mode.

6. Also, does the increased CPU speed help with CAD programs, when the OP really need is a better graphics card?

 

I've got a T9600 in a T400 and i'm not adverse to overclocking IF I can get some added performance. I just dont' know what to buy.

I run XP with 3 (sometimes 4) monitors and 3 gig of memory. I guess I should be running 3.6 gig... but even still, i'd take any increase in processing that i can get!

 

i think you should should consider a better graphics card, use a diy vidock and run the the additional monitor from that. Your bottleneck is not your CPU but your GPU.

 

DIY Vidock... tell me more... i'm all ears.

thanks!

 

http://forum.notebookreview.com/gaming-software-graphics-cards/418851-diy-vidock-experiences.html

DIY ViDock: increase gpu performance x10 - Notebooks

You can use a ATI 5870 eyefinity edition, which can connects 6 external lcd. Performance wise the DIY Vidock pretty much reaches its performance limit with the ATI 4770, as the 1x PCIe doesn't have enough bandwidth to carry all the data to and from more powerful graphics card.

 

You can now unlock the multiplier on any core 2 Extreme CPU no matter what board it is on. It's a feature of the CPU that has finally been discovered.

The performance increase is significant for minimal cost. I think many users would find that to be a good thing.

The quote I posted was an exact quote from a user that unlocked his CPU and immediately was able to gain some performance. He was very happy with that. It only took a few seconds and was dead simple to do.

The Intel TDP rating can and does cover a wide variety of CPUs within a CPU family. Here's a T8100 with a 35 watt TDP.

Intel® Core?2 Duo Processor T8100 (3M Cache, 2.10 GHz, 800 MHz FSB) with SPEC Code(s) SLAP9, SLAPS, SLAPT, SLAUU, SLAVJ, SLAXG, SLAYP, SLAYZ, SLAZD

and here's a T9900 with the exact same 35 watt TDP rating even though it has twice as much L2 cache and is running 50% faster; 3.06 GHz vs 2.10 GHz.

Intel® Core?2 Duo Processor T9900 (6M Cache, 3.06 GHz, 1066 MHz FSB) with SPEC Code(s) SLGEE, SLGKH

The TDP rating is not an accurate way to determine the actual power consumption of your CPU.

More heat is never a good thing but if you are operating your laptop on a desk then some extra heat might not be a problem at all. Intel's CPUs are rated to run 100% reliably up to 105C. Most users don't run their CPUs anywhere near their maximum safe operating temperature.

Increased CPU performance can help a lot of applications. I just wanted to provide readers of this forum with an option to significantly increase the performance of their computer without it costing too much money.

 

Actually the CPU Tjunction rating is different for Penryn and Merom processors, one is at 105 degrees and another one is at 100 degrees. But when you overclock your CPU, the Tjunction may NOT remain the same. Thinkpad would automatically shutdown at around 90 to 95 degrees Celsius.

Also, Thinkpad heatsink for CPU, GPU and northbridge are integrated together, there is only one fan to keep everything cool. If your CPU puts out too much heat, this will limit how effectively the heatsink can draw the heat away from other components, your fan would also die prematurely due to overusage. There is also the thermal soak effect if your cpu runs too hot.

All of which the users should consider.

 

dumb question: how does one unlock the multiplier to overclock?

 

Go to the hardware subforum and read unclewebb's thread.