# Laptop RAM upgrade failure
**URL:** https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006
**Category:** Factual Questions
**Created:** [August 25, 2020, 7:45pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006 "2020-08-25T19:45:00Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)
#### Post date: [August 25, 2020, 7:45pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/1 "2020-08-25T19:45:00Z")
I replaced the two gig RAM in a Dell Latitude E-6400 and an HP 620 with eight gigs. On both laptops, System gives “8 Gig RAM, 2.8 usable”.
What’s wrong?
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### Author:  [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)
#### Post date: [August 25, 2020, 8:17pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/2 "2020-08-25T20:17:35Z")
Using 32-bit Windows?
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### Author:  [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)
#### Post date: [August 25, 2020, 8:19pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/3 "2020-08-25T20:19:27Z")
64 bit Windows 7, updated to Win 10.
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### Author:  [@DPRK](https://boards.straightdope.com/u/DPRK)
#### Post date: [August 25, 2020, 8:28pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/4 "2020-08-25T20:28:28Z")
Does it make a difference in what slot you stick the RAM?
Does memtest86 successfully test all 8 G ?
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### Author:  [@blondebear](https://boards.straightdope.com/u/blondebear)
#### Post date: [August 25, 2020, 8:39pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/5 "2020-08-25T20:39:07Z")
Did you put in a single 8GB stick? I ask because some laptops have more than one slot and you need to upgrade the memory in pairs. When I upgraded my laptop (Acer Aspire) I used 2 4GB sticks in the memory slots and it worked with no problem.
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### Author:  [@Guy\_Incognito](https://boards.straightdope.com/u/Guy_Incognito)
#### Post date: [August 25, 2020, 8:48pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/6 "2020-08-25T20:48:52Z")
Have you done any BIOS updates on either laptop? It’s possible that you may need to update the BIOS so that the laptop properly utilizes the higher capacity chips that you installed.
Take another look at what blondebear suggested above, specifically the bold text.
> [@blondebear](#):
>
> Did you put in a single 8GB stick? I ask because some laptops have more than one slot and you need to upgrade the memory in pairs. _**When I upgraded my laptop (Acer Aspire) I used 2 4GB sticks in the memory slots and it worked with no problem.**_
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### Author:  [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)
#### Post date: [August 25, 2020, 9:19pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/7 "2020-08-25T21:19:39Z")
Two four gig sticks.
I’m curious that both laptops recognize that 8 gig are present, but use just over two.
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### Author:  [@FinsToTheLeft](https://boards.straightdope.com/u/FinsToTheLeft)
#### Post date: [August 25, 2020, 10:10pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/8 "2020-08-25T22:10:39Z")
> [@carnivorousplant](#):
>
> 64 bit Windows 7, updated to Win 10.
If it was a 32 bit issue, you would have been able to see 4 GB. 2.8 makes no sense.
What brand and specs for the RAM?
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### Author:  [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)
#### Post date: [August 25, 2020, 10:19pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/9 "2020-08-25T22:19:27Z")
> [@FinsToTheLeft](#):
>
> If it was a 32 bit issue, you would have been able to see 4 GB. 2.8 makes no sense.
On my Windows XP machine with 4 GB only 2.5 GB was visible.
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### Author:  [@FinsToTheLeft](https://boards.straightdope.com/u/FinsToTheLeft)
#### Post date: [August 25, 2020, 10:34pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/10 "2020-08-25T22:34:40Z")
It can depend on your video card as they mapped their address space at the top end of RAM which reduced the available addressable space for the OS. A computer as old as a Latitude E6400 wouldn’t have had a discrete graphics card that used more than 1GB of RAM.
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### Author:  [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)
#### Post date: [August 25, 2020, 11:35pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/11 "2020-08-25T23:35:47Z")
Dell’s specs, current on the web, say the laptop can take 16 gigs.
Well, they are both running Windows 10, the HP is rather slow, but the Dell ain’t bad.
Thanks, fellows.
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### Author:  [@Reply](https://boards.straightdope.com/u/Reply)
#### Post date: [August 25, 2020, 11:50pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/12 "2020-08-25T23:50:48Z")
You didn’t happen to buy on the RAM on eBay, did you? Could it be one of those hacked/fake/relabeled RAM modules?
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### Author:  [@Guy\_Incognito](https://boards.straightdope.com/u/Guy_Incognito)
#### Post date: [August 26, 2020, 4:48pm UTC](https://boards.straightdope.com/t/laptop-ram-upgrade-failure/919006/13 "2020-08-26T16:48:52Z")
As far as the Dell is concerned, you might want to check this out on their support forum:
> **[E6400 8gb RAM](https://www.dell.com/community/Latitude/E6400-8gb-RAM/td-p/7350978)**
>
> Hello, I have a dell latitude e6400. It has 2 gb ram, and I want to increase it to 8gb Ram, but it is ddr2 and not ddr3. Any ram DDR2 with 8 gb?
Definitely check which BIOS version you’re running. The examples shown on the page are both running the A34 revision level.