X-Fer from C drive to F drive slows way down during the x-fer

lilbro209

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Jan 27, 2012
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So here is what's happening...

When I transfer a large file from my C drive to my secondary internal HD ( F ) it starts at around 160mb/s which seems right ( considering I've never installed a second HD before ) but then within moments it starts slowing down around 10mb/s each second.. It will go as low as 20mb/s by the end.. Why would it do this? I don't know if I installed in right but everything seems to work fine and if I am transferring a file that is smaller then 1gb then the slow down doesn't happen since the transfer is so quick. What is wrong here?

Using Win7 64bit
i7 920
9gb DDR3
ASUS Rampage GENE 2 board
Main HDD is 1TB
Secondary is from a laptop that broke 320gb (same hook up as my main 1tb drive and by that I mean it has the 2 L shaped connectors...) as you can tell I am not very informed but I would like to be. =-)
 
First off you will always see a much higher transfer rate at the begining - Called burst rate. This is based on how much buffer ram is used generally veries from 8Mb to 64 Mbs used on some of the larger newer HDDs. Once the "buffer is filled then you drop down to the "sustained" rate which is MUCH lower than burst speed.
Sustained rate is dependent on a number of factors: RPMs, Density of the platters, and How full the drive is. Writing to a drive that is say 75% filled means that you are writing toi the inner part of the platter which is much slower than writing to the out edger of a platter.

Transfer of a large file is the sum of reading from one drive and writing to the 2nd drive. In your case you are wrting to a Laptop top HDD which are almost always slower than a desktop HDD.
Most laptop OEM drives are 5400 RPMs, desktop HDDs are 7200 RPMs. The density per platter is also probably much lower than your 1 TB "Newer" HDD.
 

lilbro209

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Jan 27, 2012
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Thank you very much for explaining that to me. Would 20mb/s ( once the burst is done on alarge file ) sound about right? The purpose of this was for extra storage but I didn't want to keep the drive in if I had it setup wrong. It seems what you said makes me think it's fine.

Since you seem to know a lot let me please ask you one more question.

Lets say I wanted to start casting/commenting on replays of certain games ok... So would I want my normal HDD running the game but have FRAPS recording to a SSD? There are people like HUSKY and DAY9 who are big in the StarCraft2 scene and all their replays are in 1080p and a smooth 30-60fps..

If what I said wasn't correct what would be the optimal way to do this? I have heard everything from 2x SSD's, 1 normal HDD to run the game and the second one needs to be a SSD, and also 2x raptor drives..

With what I currently have *My comp specs listed above* (left out the GTX260)* what would be the easiest way to get to that 1080p. Of course I know the Laptop HDD isn't going to help at all. I was thinkin the 1TB drive I have + 1x SSD to record to.Right? Ugh I am extremely tired so please excuse me if I am hard to follow. My sentences are jumbled. When I wake up tomorrow I will come back and fix this so as not to look like a complete special ed kid... =-P

Thanks in advance for your amazing help!
 

lilbro209

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Jan 27, 2012
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This is still a issue for me.

I was wondering instead of fixing this if maybe someone could go about linking me to telling me the PROPER way to install a second HD to my system.

Like I said I have a 1TB drive that came with it.. I want to add a 320GB HD that I took out of a laptop that was being thrown away. It has the same connections as my main drive ( the L shaped plugs ) and I just want a step by step guide on how to install it. It just seems when I plug it in and start using it plug n play style my comp slows down every so often and I didn't think I would have to trade storage for speed. I know I am doing something wrong.


Please Help Me!
 
HDDs are just that easy. You should be able to Power unit down, connect a 2nd HDD. turn system back on and use the system.

About the only thing that would slow you down is the Mode. a HDD should use UMDA and Not PIO mode.
Just google how to check UMDA mode: ie
Explanation (I know it deals with CD/DVD) but info also applies to HDD.
http://forum.digital-digest.com/f105/how-check-your-dma-status-reset-if-necessary-61905.html
and If your HDD is in PIO mode, then:
http://www.google.com/#pq=how+to+check+umda&hl=en&sugexp=pfwl&cp=11&gs_id=10&xhr=t&q=HDD+in+PIO+mode&pf=p&sclient=psy-ab&source=hp&pbx=1&oq=HDD+in+PIO+&aq=0&aqi=g1g-v3&aql=&gs_sm=&gs_upl=&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=39d4c75cd492ccc4&biw=1210&bih=697

It could also be that your BIOS is set to AHCI for newer HDDs and SSDs and This OLD laptop HDD is not ahci enabled. If this is the case yoiu have two options (1) remove the Old 320 and get a Newer HDD, OR (2) unfornatuatly - you live with it, your choice.