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I just bought 4 GB of ram (2x2GB) and a 1TB hard drive and installed them, upgrading from my original 1GB RAM and 250GB HDD. I put the 2GB sticks in 1st and 3rd slots and the 1GB stick in 2nd. Now with my new ram and HDD my computer is running MUCH slower and I dont know why. I've tried restarting just to see what happens and I noticed that even the Windows XP starting music is lagging. If anyone could help that would be fantastic. It's hard even to type this out.

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Is the RAM the same clock speed and CAS Latency as the original stick? You now have 5 Gig of RAM and now set to single channel (per the config explained above). Is it a 64-bit OS? What kind of spindle speed does the hard drive have? What is the cache? – JFV Sep 5 '09 at 4:47
BTW, in general, it's probably best to do a new install anytime you get a new HDD. – RCIX Sep 5 '09 at 4:54
RCIX, there are plenty of disk clone utilities that work fine. Ghost, Acronis, and there are many highly recommended free utilities. I agree that when changing a major component like a motherboard, you're probably best to reinstall, but not a HDD. – MDMarra Sep 5 '09 at 17:40

Drop the 1GB stick as you will lose dual channel mode which speeds the machine a lot.

If you have used a tool to merge one hard drive to another, you may want to run scandisk / defrag the new drive and just make sure everything is working the way it should.

If this is just a second drive, unless using IDE (instead of SATA), that shouldn't be causing these problems.

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Dual Channel Mode has been proven over and over again to deliver extremely insignificant performance improvements. Do not drop the 1GB, more RAM is better. – caliban Sep 5 '09 at 8:06
Scoop, dual channel can improve performance by as much as 15-20% in certain situations. Having 5GB RAM in a 32-bit environment is actually a total waste. – MDMarra Sep 5 '09 at 13:04
@caliban: A 32 bit OS can only access around 3.5GB of RAM. Therefore the extra GB is not helping at all. – Macha Oct 18 '09 at 16:44

Well, first of all you should run just the 2GB sticks, you probably don't have XP x64, so the additional GB does nothing except drop your RAM out of dual channel mode. That alone shouldn't cause this problem though.

Did you add the 2nd HDD as a secondary drive, or did you use a disk clone utility to move the contents of the 250GB to the 1TB?

Open task manager, make sure "Show Processes from all Users" is checked, and sort by CPU usage, what is taking up the most CPU. Also, what does it tell you about your RAM, is it full, or do you have some headroom.

Are these the only two things you upgraded?

What is the make/model of your computer. If it is custom built, what is the hardware in it?

Does this slowdown still happen in safe mode?

Have you used a RAM testing bootable utility such as memtestx86+ from ?

If you remove the new RAM and HDD, does this still happen? If it doesn't, add the components one at a time, until you can find out what the culprit is.

You need to do some basic troubleshooting before anyone can even begin to guess at the problems you are having.

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I have had this persistent problem with my PC and it is accompanied by choppy sound. It seems the HDD defaults to PIO mode if there are too many communications errors. I fix it by unistalling my ATA/IDE drivers under "Devices" but it is a temporary solution since after a while teh comm errors build up and the machine goes back to PIO mode.

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Check your motherboard. It may only be capable of handling 2GB of RAM, especially if it's an older XP computer. (My old Dell PC could not understand more than 2GB)

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Download Process Explorer. While Process Explorer is running, do something that takes a long time to run. Note which process is taking all the CPU. If it is a process called Interrupts, then your hard drive needs to be set to a DMA mode (it's probably running in PIO mode).

Read here on how to revert back to the DMA mode. Mostly, you can take care of the problem by running this script and then rebooting the box.

Finally, you honestly do not need 5 GB on a Windows XP 32-bit edition, though it is most likely not the problem here. Remove the 1GB stick, it is totally superfluous. The only use I could see for it is if you want to use RamDisk Plus from SuperSpeed - it does let you create RamDisks that utilize memory from the beyond the 3.5GB limit.

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Check, in Device Manager, to make sure that Windows is using UDMA moed to access the new drive, and not PIO - this would cause a massive reduction in apparent drive speed while simultaneously consuming extra CPU time for IO operations concerning that drive.

If Windows has dropped the access mode to a lower standard it may just be a "random" glitch due to the change of hardware between boots. It may also be because it has experienced IO errors communicating with the drive. In response to certain types of error it will drop the IO mode down a level and retry so you may not have had noticed of the condition. I suggest checking the SMART logs of the drive closely and performing a full test (drives can perform self-tests, which must SMART related utilities will be able to kick off, I also suggest a full surface scan).

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