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I have an old Acer Aspire T180 desktop. The specs are as follows:

  • AMD Athlon 64 3800+ 2.4GHz
  • 160GB
  • DVD-Writer (DVD±R/±RW)
  • Gigabit Ethernet
  • 17" Active Matrix TFT Color LCD
  • Windows Vista Home Basic
  • Mini-tower
  • AST180-UA381B

According to the information in the computer's documentation the computer comes with 1 GB of RAM. It has two DDR2 SDRAM sticks. I used to have Windows Vista installed. Then I removed it and install Windows 7, and now I have since removed Windows 7 and installed Windows XP.

According to Windows XP with both RAM sticks in the computer has 768 MB. Isn't this supposed to be 1 GB of RAM or 1024 MB of RAM? Is the amount of RAM installed only partly used by the Operating System? Is there's something I'm missing?

If I remove either one of the RAM sticks I'm left with 448 MB of RAM. These numbers don't seem to add up. If each of the RAM sticks contains at least 448 MB of RAM shouldn't they (both being in) provide 896 MB of RAM. Even then, isn't that less than a GB of RAM?

I'm not too experienced in hardware so I thought this would be the best place to ask.

As a follow up question, is the RAM I have enough to run/multitask with Windows XP efficiently? I plan to do a lot of computing with the system (although not gaming), should I invest in more RAM?

share|improve this question
(random guess, not sure if relevant) it could be allocating the rest of the memory to your graphics. – cutrightjm Dec 1 '12 at 3:05
1GB is sufficient for XP, and 2GB is great if you are a very heavy user. yes 1GB is 1024MiB. ekaj has a good hypothisis; is your bios set to automatically allocate video ram? if so that would explain why things aren't matching up. with only 512MB ram, it might allocate 64MB to the vcard, but with a GB, might allocate 256 as you are seeing. – Frank Thomas Dec 1 '12 at 4:38
How can I check how much RAM is being allocated to the graphics card. I can't find any kind of option in CMOS under Advanced Chipset Features. My computer runs Phoenix - Award WorkstationBIOS CMOS Setup Utility. Any advice on how to confirm your theories? – Nathan Taylor Dec 1 '12 at 9:11
up vote 0 down vote accepted

I would suggest using the free Speecy utility to check out your system. It can provide amazingly detailed information about the sizes and types of RAM modules installed in your system.

If it turns out your graphics card is using up some of your RAM by sharing it (as looks the case like from reading the specs for your system), you can either get a new graphics card that has its own memory or get additional memory to fill up the two empty memory slots available. It's not entirely clear which would be your best option from the information you provided.

share|improve this answer
Thanks! I examined the RAM section on Speccy and it doesn't really tell me how much RAM is allocated to the graphics card. I may be missing something. – Nathan Taylor Dec 1 '12 at 15:08
@TaylorND:The graphics your machine are from an nVIDIA GeForce 6100 256MB Shared DDR2 SDRAM Integrated which is not a separate graphics card but an on-board graphic chip which is "sharing" or using 256MB of your 1024MB which why you only have 767MB left over of the OS and programs. This agrees with what is being shown by Speccy. Here's some detailed info about the GeForce 6100 motherboard chip. – martineau Dec 1 '12 at 17:47
Awesome, thanks for the help. So when an Operating System documentation says it needs at least a GB of RAM to work well does it mean the RAM left over for the OS and programs or can I count the RAM being shared with the graphics chip as part of that requirement? – Nathan Taylor Dec 1 '12 at 19:53
@TaylorND: It usually means what's left-over (as in not being shared) and available. That said, what you have is probably good enough for running XP as long as you're not gaming. The GeForce 6100 provides only entry-level graphics capabilities. Indeed the Aspire T180 desktop is a basically what I'd consider to be a somewhat low-end system. You could get a separate graphics card for not very much more money and free-up that 256MB currently being used. I'd wait and use the system for a while before deciding anything. BTW, would you consider accepting (and hopefully also up-voting) my answer? – martineau Dec 1 '12 at 21:14
Of course. I'm new to the stack exchange, how exactly do I do that? I clicked the check mark beside your original answer on Speccy, and when I tried to "vote up" it told me I needed 15 reputation. Your answer was a great, great help to me and I'd like to vote you up for it. Thanks. – Nathan Taylor Dec 1 '12 at 23:47

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