PDA

View Full Version : Memory upgrade and Paging file.


fradu
22nd Aug 2007, 09:08
Hello there,
I am hoping for some advice on RAM and Paging file sizes!
My PC specs...

- Asrock ALIVENF6G-DVI Skt AM2 Nvidia NF6100-430 onboard 256MB shared VGA 8 channel audio mATX
- AMD Athlon 64 X2 4200+ Socket AM2 (2.2GHz) L2 1MB (2x512KB) Processor
- 2 x 1GB DDR2 667MHz PC2-5400 RAM
- Seagate 320GB Hard Drive SATAII 7200RPM 16MB Cache Hard disk (partitioned 60Gb/100/120Gb)
- Windows XP Home SP2 OS

I am considering upgrading the RAM to 4Gb, but have become aware that there is a chance that XP Home will not recognise it fully?
Does any PPRuNers have experience with this issue, and would you recommend me upgrading the memory?
My motherboard recommends I run RAM in pairs, so would 3Gb (2 x 512Mb and 2 x 1Gb) be acceptable, or would that not be fully recognised by XP Home?

Onto paging files, mine is currently set to an initial size of 2976Mb (1.5 x RAM) and maximum 5952Mb (3 x RAM) stored on C drive.
Are these figures oversized? I don't really want to run without a paging file or one that is of minimal size, as I have had problems with RAM before, but 5952Mb does seem a bit large to be handing over!
The PC is used for a bit of gaming, web-design and multiple Adobe Photoshop file edits (all open at one time), plus the usual Office, Antivirus/Firewall/Spyware programs that run in the 'background'.

Any advice would be appreciated, and I hope I've covered everything.
If not, please feel free to shout!

Many thanks for your time.
Mark

Saab Dastard
22nd Aug 2007, 10:35
With XP Home you cannot allocate more than 2GB RAM to applications - you can allocate 3GB with XP PRO, however.

See this MS article (http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx).

Personally I regard 2GB as a practical max (certainly for XP home). Add more if you wish, but it will be of questionable value.

Read the mobo manual for how to add RAM - it may be that you can add RAM in pairs to improve performance, but it is probably not necessary, so you can have an odd number of DIMMS, or DIMMS of different sizes.

You should accept the page file size Windows recommends - unless you have good cause not to. What's 6GB out of 320? For performance, don't put it on the system partition, don't spread it over multiple disks and do make it a fixed size (to help avoid fragmentation).

SD

fradu
23rd Aug 2007, 09:04
Thanks for the advice!
I have given the paging file a roomy 20Gb partition all to itself now (a newly created X: drive).

However, my Diskeeper program recommends that I still have a paging file (no matter how small) on the system partition!
I've not created one, but why would they recommend it?

bnt
23rd Aug 2007, 13:28
Windows will pre-load up stuff it doesn't necessarily need to, with different priorities. There will usually be some swapping to pagefile, even if you have 2GB installed and there is almost nothing running, which is a minimal performance hit.

I wouldn't worry about it - treat it as a "just in case" thing, because the consequences of Windows suddenly running out of memory can be pretty nasty. For example, I've seen graphics-heavy web-pages cause Firefox to grab hundreds of MB, in no time at all - instant thrashing, but the system stayed up...

Saab Dastard
23rd Aug 2007, 14:37
However, my Diskeeper program recommends that I still have a paging file (no matter how small) on the system partition!
Bollocks!

I am not aware of any such requirement, and I have not had a swapfile on the C drive for years!

The only reference that I can find for this is for "an emergency" - what sort of emergency is that then? If a disk containing the pagefile has failed, you probably aren't going to be worrying too much about the state of the page file! You are probably more concerned about the failed disk and all the data that's on it!

It is, however, true that you cannot have a pagefile larger than 4095 on any single volume; this limit is imposed by the page mapping that MS use on x86 processors. These processors cannot handle more pages per page file and so to have swap space greater than 4095 you would need to create pagefiles on multiple volumes (or in multiple folders on a single volume).

The recommendation from MS is that the size of page file is 1.5 x actual RAM for RAM < 2 GB and 1 x actual RAM for RAM >= 2 GB. So a 4 GB pagefile is still fine for the max. supported RAM.

There is more here (http://support.microsoft.com/kb/237740) from MS.

Note that there is actually a slight perfomance gain in spreading the paging file over more than 1 physical disk, but a performance penalty in spreading it over multiple partitions on a single physical disk.

If you only have one disk, leave it on C, or create a dedicated partition. If you have more than 1 disk, put it on the non-system partition disk.

Creating a decicated partition for the pagefile does not help with fragmentation of the page file, however it does prevent the pagefile contributing to fragmentation on other partitions. Creating a fixed-size pagefile does help prevent fragmentation of the page file.

More here (http://www.petri.co.il/pagefile_optimization.htm).

SD

Mac the Knife
23rd Aug 2007, 15:38
XP (Home or Pro) benefits little from much more than 2GB RAM.

Not worth it.

Save the money and take your wife/GF out to dinner - the results are usually much more gratifying...

:ok:


SEO by vBSEO 3.6.1