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My dear Dell Inspiron 1545 keeps getting old and slow on me. I have replaced my old HDD hard disk with a new SSD one and replaced the old 6 cell battery to a new 9 cell one and while indeed the machine was faster and every battery session was longer , yet , it remained a bit slower that what I expected. To simply put it - I wanted more speed, more performance , less power up times and less wake up time from hibernation.
It was time for a new CPU.
After roaming the web researching what possible CPU can I upgrade to along with looking at my laptop's manual , I came up with the conclusion that I can upgrade to a very narrow line of CPUS based on the following facts:
- The CPU should be a socket P CPU with 478 pins
- Up to 3MB cache
- Up to 1066 rated FSB
- Core 2 duo , Celeron , Celeron Dual-Core , Pentium Dual-Core
My current CPU was a mid-range decent T6400 CPU that has 2MB cache , runs on a 2.00MHZ frequency and 800mhz FSB. I needed an upgrade that would dramatically increase performance , lower power consumption and heat dissipation and that would come with a decent price tag, otherwise it wouldn't be economical to do this upgrade at all…
After browsing Intel's CPU database (ARK - http://ark.intel.com/), based on the following screening - MOBILE PRODUCTS >> PROCESSORS>> Intel® Core™2 Duo Mobile Processor>>3MB cache>>frequency higher than 2GHZ ( here is a direct link with the filter values submitted - http://ark.intel.com/search/advanced/?s=t&FamilyText=Intel%C2%AE%20Core%E2%84%A22%20Duo%20Mobile%20Processor&ClockSpeedMhzMin=2000&ClockSpeedMhzMax=4000&CacheKBMin=3072&CacheKBMax=3072), I narrowed down my upgrade options to the following
- The best option was the - Intel® Core™2 Duo Processor P8800
(3M Cache, 2.66 GHz, 1066 MHz FSB) - Under that - Intel® Core™2 Duo Processor P8700
(3M Cache, 2.53 GHz, 1066 MHz FSB) - In the 3rd place there was an even more weakened P8800 - Intel® Core™2 Duo Processor P8600
(3M Cache, 2.40 GHz, 1066 MHz FSB) - And a T - series CPU - Intel® Core™2 Duo Processor T8300
(3M Cache, 2.40 GHz, 800 MHz FSB)
The other options were too slow in comparison to the best option (P8800) and their clock speed wasn't higher enough from my current 2GHZ CPU clock speed to create any noticable major improvement in performance.
Of course there were other options as well under the 2MB cache filter , most of them wereT-series processors, so , as a skilled consumer I continued my research and this time I was looking to find out what is the difference between the P-series processors and the T-series processors.
T-series VS P-series:
I soon found out that the P-series processors were more energy efficient and had lower TDP (Thermal Design Power) than the T-series processors. Less TDP means less heat dissipation, less heat dissipation means less CPU fan cycles and better CPU performance and less CPU-FAN cycles means lower battery consumption.
So I went along with the P8800 for several reasons:
- The price gaps between the weakened P8800 (P8700, P8660) were very small
- The P8800 itself wasn't too expensive (its launch date is February 2009 , quite a lot of time has passed since then)
- It presented the maximum upgrade features - 2.66GHZ , 3 MB cache and 1066MHZ FSB - in a very low price tag
- Lower TDP
Installation Process:
I have a lot of experience replacing CPUs in desktop machines, but this was my very first laptop CPU upgrade. In order to get myself ready I watched this video - http://www.youtube.com/watch?v=kL9z2uFBjkU
Overall , the process Is very simple:
- First of all I took the battery off completely
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- Pushed the power button steadily to release any static currents that were present inside the machine
- Unscrewed 4 Philips screws out , the screws hold the CPU, RAM and WIFI card cover in place.
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- 4.After the screws were out , taking the cover itself was a bit hard, after all , it was the first since I bought this machine I attempted to take it off. A used some carefully measured amount of force to get it free using my fingers only (no tools!)
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- The opposite side of the cover was very filthy with dust so I cleaned it
- After the cover was out the RAM, WIFI card , CPU and North bridge were revealed , it seemed that the CPU and the North bridge were using the same heat pipe
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- I unscrewed the single screw of the North bridge first
- Afterwards , I unscrewed the 4 surrounding screws around the CPU, holding the heat pipe assembly tight over the cpu
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- After all the 5 screws were out, I took the entire heat pipe assembly out, this part was a bit tricky. The heat dissipation ribs refused to get out from its position , unfortunately I used a flat screwdriver to try to get it out and later on I found out I bended some of the ribs a bit , so no matter how difficult it seems - DO NOT USE ANY HARD TOOL TO REMOVE THE HEAT PIPE ASSEMBLY. A little measured force with my fingers did the job after some time along with patience.
- After finally the heat pipe assembly was out I noticed the result of over 3 years of fan use - a big chunk of dense dust that accumulated over time between the heat dissipation ribs and the CPU fan. This dust chunk in its current form was probably present there for some time, blocking a significant amount of air coming from the fan. No wonder my laptop was so hot all the time…
- The CPU was revealed , the white material around it is a heat conductive paste. I unlocked it by twisting the big flat screw all the way to the left. There is actually a carved writing on the pink plastic that says which side is to open and which is to close (or lock) the CPU. Right = close , left = open.
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- It was very hard getting the CPU out. I thought more than once that I might have done something wrong or didn't twist the flat screw all the way to the left. Again, over 3 years of use did their own, and the CPU got literally glued to the socket , I used pure measured force and finger power to get it out, when it finally did, it got released at once very brutally.
- After seeing the huge dust chunk I took to chances. So I took my vacuum cleaner and sucked every mm of the fan's intake and exhaust holes and the heat dissipation ribs.
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- Finally I took the new CPU out of the box only to discover that the seller put a big sticker with Chinese writing. I took it out not because of aesthetics , but because it could interfere with heat dissipation. Taking it off was very annoying. It was glued quite well right over some crucial transistors. I used a small 1mm flat screw to gently remove it.
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- I put the new CPU in the socket
- Smeared some heat conductive paste over the CPU core and over the parallel area on the heat pipe unit. I used a simple swab to smear it.
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- I put the heat pipe assembly back, and the 5 screws back
- Returned the cover back , screwed back the 4 screws of it.
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- Put the battery back
- Connected the power charger , powered on , and walla!
Results and performance:
- Boot up time decreased noticeably
- Restoring a Firefox session with over 200 tabs was done faster than ever
- Editing large photos (4000X3000 pixels) was done faster
- Wake up time from hibernation (when the laptop's screen is closed) got faster
- In power saving mode , battery life was increased in at least 40 minutes
- Windows Experience score stayed the same due to the lack of a change in graphic card (GMA4500)
- Heavy applications like Photoshop CS6 open up significantly faster
Conclusion:
It was definitely worth it , the low price of the CPU, the easy installation process and the result made this upgrade very beneficial and worthwhile.
CPU price - 39.99$ in E-Bay
Pros:
- Better performance , faster boot up time , handles heavy applications faster
- Lower battery consumption, power saving , lower TDP
- Brings new life to your old laptop and extend its use
- Easy installation process
Cons:
- Quite limited range of possible CPU upgrades , none of the CPUs that are out there can be used with this laptop (quad cores for example , CPUs with smaller lithography)
- In power saving mode , clock speed drops down to 800MHz while in the previous T6400 CPU it dropped to 1600Mhz. this is very annoying especially if you shut down your laptop in power saving mode and turn it back on again - Vista would boot up at 800Mhz….very annoying, however , I'm sure there is a way to change that setting inside Windows.
