Best RAM for old dell?

[zachbb]

Hi

I would like to upgradeb the RAM on my grandmother's old Dell Dimension E521 Athlon 64 3800+.

Currently, there are 4 sticks of 512MB PC2-4200U.
The motherboard is: Dell Inc 0HK980 A01
Board serial number: ..CN7082169BE0H6.
Bus Clock: 1000 megahertz (according to BelArc)
BIOS: Dell Inc 1.1.11 08/02/2007

My question is:
1. What is the fastest RAM I can get for this system? 4200, 5300 or 6400?
2. Is there a limit on how much ram I can fit in it? Or can I just get the biggest sticks I can find?

Thanks!

Zach

 

[jaquith]

Here's RAM for the Dell Dimension E521 - http://www.crucial.com/store/listparts.aspx?model=Dimension%20E521&Cat=RAM

Assuming it's 32-bit OS then 3.0~3.5GB will be usable to the OS, and it has a 4X1GB limit. 2GB is okay for XP 32-bit and the additional RAM may not prove to be a 'gain in speed' however if there are a lot of startup items then yes there will be a gain IF in the Task Manager 'Commit Charge >1500M ~ 1700M'

ANS1 - PC2-5300 is the fastest the Dell allows, this is a BIOS issue. Dell locks-down the DRAM/Memory Frequency and it's not modifiable by the user so faster RAM is simply under-clocked. You can access the BIOS and double-check.

ANS2 - The limit is 4GB 4X1GB with a maximum of 1GB per DIMM slot; not the usable limits above.

 

[zachbb]

Thanks so much for the reply.

Can I mix and match ram speeds? I have 2 sticks of PC2-5300 from another computer that I'm not using. Can I have two of those and leave 2 of the PC2-4200 in there at the same time?

 

[jaquith]

Probably not if different CAS - the JEDEC '533' {267 MHz CPU-z} on both sets would need to match, and defiantly not if they have different Voltages. In general it's not the best idea.

Use CPU-z, look at the 'SPD' tab and compare both sets -> http://www.cpuid.com/medias/images/en/softwares-cpuz-05.jpg

You can 'try' the mix and see what happens. If the PC boots fine then the next step is to run Memtest for at least a couple of hours; create a bootle CD/DVD use the ISO/zip file -> http://www.memtest.org/

I just looked at Dell's site and it has something different than Crucial; once in a while the 'specs' don't match -- so I choose Dell over Crucial; see - http://support.dell.com/support/edocs/systems/dime521/en/SM_EN/specs.htm
Memory Type: 533-MHz, 667-MHz, 800-MHz (when available) DDR2 SDRAM

So my revised answer:
ANS1 - [strike]PC2-5300[/strike] is PC2-4200