Dell Studio XPS 1640 1645 Serial Flash CMOS PINS

Dell Studio XPS 1640 1645 Serial Flash CMOS PINS

Help is needed to know which or both of the two Serial Flash CMOS ICs are to be used to clear the CMOS and BIOS passwords on a Dell 1640.

The process to be used appears credibly outlined at the following web address: http://www.darkmagic.org/mike/dell-tag/dell/dell.html

But the laptop used in the above web site is not that of a Dell Studio XPS 1640 or 1645. So parts location, disassembly and reassembly are unique with the 1640 & 1645.

I have had the 'privilege' to be stonewalled by Dell 'customer service' when requesting the lost password to access CMOS & BIOS setup on my Dell Studio XPS 1640. I purchased a used Studio XPS 1640 that was just under 2 months out of warranty from another who was disgusted with the hassles that have developed with some of the 1640s & 1645s over heat, throttling, RGB screen blinking, inadequate power supply, etc, etc. The formal transfer of ownership was immediately completed on Dell's web-site.

The Dell customer service representative was inflexible & obstinate. They would not release or help me with understanding of how to remove or change the CMOS password other than to hold the info hostage subject to my first purchasing a ~$240 one year warranty or forking over $49 for the password without any additional warranty. I know this is common Dell practice, but it seemed inappropriate by Dell given the short time of the expired warranty and the fact that I have had 4 earlier Dell laptops (XPS2, 9200, 9100, & 8600). The action of the Dell CSR eliminates any future loyalty to Dell from me. To put it mildly, I was/am PO'd.

My plan is to swap the P8600 and 1640 motherboard with a 1645 motherboard and i7 mobile CPU. My objective is to sell the 1640 motherboard and P8600 to recoup some of the conversion costs. I do not want to sell the 1640 motherboard and P8600 until I know the 1645 conversion is working without major issue. I am not willing to sell the 1640 motherboard until the CMOS/BIOS password(s) are removed and do not seek to attempt the 1645 conversion until the 1640 CMOS password issue is resolved. I understand that it would be simpler to just cough up the $49 ransom, but isn't it better to attempt to resolve the issue so that all may take advantage? Where is the fun is adding to Dell's income when they are attempting extortion in the belief they can shake you down?

It did not look wise to pay Dell for the password or warranty at this time. Since the plan is to clear the 1640 CMOS then remove the motherboard and CPU to replace with a 1645 motherboard and i7 CPU, a warranty would certainly be viewed as later invalid by Dell. If successful, perhaps this data will also aid others and reduce the coffers of Dell from its laptop users who simply need help instead of Dell's (miserly) hand in their pocket. If unsuccessful, I will pay the $49 for the password.

It was silly of me to anticipate any action from Dell other than that I received after a review of web requests from many others on all series & versions of reasonably current Dell laptops. This CMOS password issue appears to be one of the most common desires of Dell laptop owners following Dell's move to serial flash CMOS.

There is considerable good information on the web but nothing I found that directly applies to the Studio XPS 1640 or 1645 due to Dell's use of Serial Flash CMOS. Current available software does not deal with the Serial Flash CMOS password issue.

Here are two web sites that do appear to have good information. The first site is especially helpful to me but concerns another Dell laptop model. http://www.darkmagic.org/mike/dell-tag/dell/dell.html
http://www.weeklygripe.co.uk/a709.asp. Must confess that these guys are smarter than me and do appreciate them taking the time to describe their methods and experience. It appears the first site describes a straight forward path to success other than knowing how to handle the presence of two Serial Flash CMOS ICs.

So far, their information has been used & updated by the Dell Studio XPS 1640/1645 on-line Service Manual: http://support.dell.com/support/edocs/systems/sxl1645/en/sm/index.htm
Be careful to follow the Dell service manual precisely on both tear down and reassembly.

The web data located here ( http://www.darkmagic.org/mike/dell-tag/dell/dell.html) provides details on how that author found and removed the CMOS and BIOS passwords within the Serial Flash CMOS by use of a paper clip and the Dell service manual. The process includes shorting two pins of the CMOS IC chip at start-up. The start-up timing is shown on one of the PDF graphs as allowing that time only as the opportunity to "flash" or "corrupt" the CMOS password. This appears to be a 'do-able' approach for Dell laptops where more typical software procedures do not work, as with the 1640 & 1645.

My 1640 is disassembled to the point that I need to better understand which (or both) of the serial CMOS chips and what pin numbers to use to clear the CMOS and BIOS passwords on the laptop.

Would one of you, more knowledgeable than me, guide the correct solution?
It is not the purpose of this web content to promote, assure, or condone this or any procedure as being safe or reasonable without the use of appropriate devices or methods. Anyone performing this or any similar procedure is responsible for seeing to the safety needs of and resulting from such a procedure.
Furthermore, on the subject of Electrostatic Discharge (ESD,) and potential damage to computer chips or circuitry: Apart from volatile memory (SIMM / DIMM modules), I have never used ESD reducing devices, nor known any computer device to fail due to the effects of ESD from handling or use without ESD reducing equipment. This may, in part, be because I live in an area where the average humidity is high. I understand that increased humidity may tend to lower ESD effects, while lower humidity tends to increase it. Anyone deciding to perform this procedure must make their own decisions about the importance of ESD in their environment and the need for special devices or procedures.
(Remember that SIMM / DIMM memory modules / sticks are always extremely susceptible to ESD damage at any humidity, under any environmental conditions, and should always be handled with the utmost care and precaution against damage.)
Dell Studio XPS 1640 / 1645 Specific Data

On my Dell Studio XPS 1645 motherboard, there are two (2) Serial CMOS integrated circuit chips on the "DIMM side" of the motherboard and located just below and to the side of the PM55 Chipset Platform Controller Hub. Dell uses the Serial Flash CMOS ICs to make it difficult for users to access and/or remove the set CMOS and BIOS passwords.

Also note that these same serial CMOS chips are where the tags: service, asset, owner etc are located. Dell technical support may not overly assist you without a service tag for example, so do not lose your existing service tag - you may need to also insert this once again and validate the set up (once complete) with Dell technical support to make sure your and Dell records are in agreement.

On my 1645 motherboard, the two Serial CMOS chipsets are labeled as follows:
MX-12G 25L3205DM2I 38730300 TAIWAN L094236
MX-15G 25L8005DM2C 3C0JS800 TAIWAN Z093514

If interested, you may Google "MX25L3205DM2I-12G 16M-BIT [x 1 / X 2] CMOS Serial Flash" and "MX25L8005M2C-15G - 8M-BIT [x 1] CMOS Serial Flash" to discover PDF documentation on each of the two chips, the opportunity to purchase the chips in 11,000 quantities (!), etc.

An example of the nomenclature of the chips is as follows (data found on the documentation PDF):
MX25L3205DM2I-12G
MX Model Type
25 Serial Flash CMOS
L 3.3 Volt
3205D 32mb Density & Mode
M2 200mil: 8-SOP Package
I (I)ndustrial Temperature Range (Note: C = Commercial)
12 86Mhz Speed
G Pb-Free Option

Check out page 47 of 56 from this PDF: (note to follow the site instructions if initially the PDF does not appear)
http://pdf1.alldatasheet.com/datasheet-pdf/view/267918/MCNIX/MX25L3205DMI-12G.html

On my Dell 1645, the two Serial Flash CMOS ICs are 8 pin devices (4 on each side). Be wary about planning to replace the CMOS ICs. This is a tedious and dangerous process. The pins are close together and the motherboard can easily be damaged due to the required heat on the multi-layer board. Unless you are genuinely an expert (not just good) at soldering, DON'T DO IT! eBay has had multi-pin versions of these devices that will NOT work on the 1640/1645. Also other 8 pin versions exist for other purposes and will not work on the Dell 1640/1645. Avoid making a mistake.

The PM55 Chipset is identified as BD82PM55, with subcategories of SL6WN , J9368043, and 88 on the PM55 chipset. The chipset mount is the large green platform also near the black UWB label.

The CMOS and Bios passwords are located within one or both of the two Serial Flash CMOS ICs.

Help is requested to identify which or both of the Serial Flash CMOS ICs to short pins at startup in order to clear the CMOS and BIOS passwords. Pin numbers to 'paper clip' short are also needed although they may be properly described in the first web site addressed.

Once successful, I will post the specific steps for the Dell 1640/1645 and include pictures to help others.

Thanks in advance for any assistance!!!

Terry

 

Instead of going it that way... consider:

1. Dell service cd, you need to get it from a tech as they use them to replace the service tag after motherboard replacement.

2. Another bios authority software

3. Disconect the AC, remove the system battery, the cmos battery and hold the power button for 30 seconds.

 

also if your planning on doing that conversion you will need a base because not all the holes for the screws will line up