Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.

Windows 7: Is it possible to create a C: drive with 64K clusters?

13 Aug 2009   #21

Win7 x64 RTM

Quote   Quote: Originally Posted by kolotyluk View Post
Sounds like what I'm looking for, but can you please give me some more details. Will windows automatically create the boot partition? Should I just leave 100 MB or so before the C: partition?
I was experimenting with stripe size after reading some obscure posts concerning raid5 performance on my nvraid. As an old time network engineer, I grew used to putting fast scsi raid5 setups on servers, and getting amazing performance along with data protection. My ASUS M3N78-VM motherboard supported raid5 on the SATA2 bus, so I installed there but found a distinct lack of the performace gains expected of a raid5 controller.

I was preformatting my attempts with a separate drive with XP on it for my tests. The "System Reserved" partition does not have to be before the C: partition. At one point I had a build with OS, them system reserved, then data.

A side note, even a single large disk as I am currently using a 500gb drive to boot on usues a 100mb System Reserved partition to boot, even though I am now using standard cluster sizes.

So go ahead, wipe the drive completely, start your install and drop to command prompt to preformat. Just be sure to leave at least 100mb unused on the disk when you create your OS partition. Win7's install will create the System Reserved partition in the free space.

My System SpecsSystem Spec
20 Sep 2009   #22


umm... this works with Vista and SP2 (not SP1) and i tested and confirmed it working on Win7 (i posted this last year actually)

During Win Install Shift F10:

select disk 0
create partition primary size=35174
create partition primary size=128 (i didnt actually have to put size as that was all that was left anyway)
select partition 1
format fs=ntfs label=Alpha quick unit=64k
assign letter=c
select partition 2
format fs=ntfs label=Omega quick unit=4k
assign letter=d
list partition (both Partition 1/2 show up)
list volume (shows my CDROM then shows C: as Alpha -34GB- and D: as Omega -128MB- good to go right! )

this was on my old WD Raptor, I have since upgraded to a bigger drive and used this method again (adjusting size of course for new HDD)

(also i signed up just to reply to this over a month old post... sad isnt it) :/
My System SpecsSystem Spec
21 Sep 2009   #23

Windows 7 Ultimate 64-bit

Thanks Kane for showing me another way to partition the disk, but the problem I have is the Windows 7 installer - it reports an error when the c: partition has 64K clusters.

Have you actually been able to install Windows on such a layout?

Cheers, Eric
My System SpecsSystem Spec

22 Sep 2009   #24


Yes this worked for me perfectly, you have to follow those commands exactly pretty much (except the size)
My System SpecsSystem Spec
15 Oct 2009   #25

Windows 7 x64

I am very interested in using the 64k block allocation as well. I have two new unformatted WD Velociraptor drives (a 150gb and a 160gb) I want to use the 150 for my C drive (for Windows 7 x64 and other programs) and the 160gb drive for my Flight Simulator only. (will call it F drive..)

I have read in sim forums (and from a knowledgeable administrator) that using a dedicated physical hard drive (and not a partition) for the sim with a format of 64k block allocation (particularly with the WD V-raptor drives) helps alot with faster or more efficient scenery loading. I use up to 100 gigs of scenery alone so I assume much of the individual files are rather large. There is alot of advanced detailed scenery available now so I assume the 64k allocation for F: alone will be a good thing.

However, would also setting the up C drive with Windows 7 x64 and 64k blocks have any added benefit or is "block size matching" between these two non RAID drives even an issue worth hassling with? A caveat here is I will also install several sim related programs on the C drive that will need to reference the other drive (F) while in flight hence my main concern for having both C and F set to the same block sizes.
My System SpecsSystem Spec
16 Oct 2009   #26


replied to your PM, hope it gets to you ok :)
My System SpecsSystem Spec
17 Oct 2009   #27

Windows 7 x64

Kane, I got your reply but could not PM you back for some reason. It seems this forum doesn't like you to keep messages as my inbox was full with our one exchange. So, if you can, and are willing please send me your regular email in a PM if you dont mind. The pics you saw on my website are 5 outputs/3 video cards/1 PC. --My regular email is also found on the home page of my website.

As far as my sim file sizes go I am having to get that answered from a freind. My PC is awaiting this format based on my/our decision on block size and therefore I have no way to look at files that are not yet installed ! (Im writing from my laptop)

Again, I routinely install 80-100 gigs of data with the typical NTFS 4k blocks as I have never attempted anything aside from stock/default formatting procedures. I had just read a tutorial from a sim forum moderator that specifically recommended formatting your sim specifics drive at 64k. So what I really need to know is would the 100gigs of my typical install far exceed the capacity of my 160gb drive? (if set to 64k?) --- Should I get a 300gig Velociraptor instead?..or is 32k an acceptable compromize for both drives? --I imagine these file sizes for the sim will be completely random from a few kb up to several MB per scenery file. For instance a "pack" of scenery for say Southern California may be 5gigs total but will be comprised of at least a thousand ".BGL" files for instance, which all vary in size. Hope that helps.
My System SpecsSystem Spec
18 Oct 2009   #28



PM is on its way
My System SpecsSystem Spec
04 Jan 2010   #29


Both Vista and 7 'usually' work well with C: drive being 64K clusters, and boy
does it run fast. As others have posted, one needs to be sure to have
a separate 'system boot' partition.. That one MUST BE 4K clusters, or
the boot loader will not work.

As others have said, you can interrupt the windows install, and first format
the future C: partition with NTFS 64K clusters, or use Acronis Disk director
to format with 64k clusters, etc.. and windows7 will install ok and leave
it at 64k. Just don't mess with the boot partition cluster size.

For an after the fact '64k cluster upgrade', assuming you have a 'system boot'
partition, and your C: drive is 4K cluster, you can boot up Acronis Disk Director
or equiv and change it to 64K cluster. Be sure to make a backup before.

More likely than not, your system will not boot after this change. Insert
the win7 install disk, and initiate a startup boot repair.. may take 2 or
three attempts, and then it should work fine.

The reason I said this 'usually' works, is that I have some issues on one
system on an Areca-1221X raid controller (8 drives). It runs ok for
5-60 mins (even setting idle), and then takes a disk hang.

O&O drive LED3, shows C: hanging with pending I/O ... things which don't
need I/O keep working for awhile, and eventually hang also. Need to
reboot to clear. I would take a wild guess that this is paging I/O, since
other partitions are 64k clusters and don't hang. O/S is win7 x64.
Put it back to 4K cluster and it seems to have cleared up.

Of course, it might be an Areca driver issue also. I doubt that 64k cluster
C: drives are officially supported, so we probably don't have a leg to
stand on about griping to someone. In the past, Microsoft has gone
out of their way to make 64k C: drives difficult on XP and Vista.

There also may be some issues on bitlocker encryption and file compression.
From memory, this summer with WIn7 Beta Rc1 or such, with a 64k (cluster)
C: drive, I think bitlocker (drive encryption) still worked, but file compression
did not. If one compressed files (show up as blue), when drive was 4K, and
changed to 64k, then previously compressed files could be seen and
decompressed, but no new compressed folders could be created.

Seem like minor annoyances in return for the extra I/O speed of 64k.

My System SpecsSystem Spec
05 Jan 2010   #30


i know i posted the solution to this a while back... now i just wish i could remember how it can be done in XP... i forgot (their was a trick to it...) totally... /cry

anyway, a thought might be to check the block size for that specific raid controller? is it 128k like most? try 32k then instead of 64k...

or try exFAT (64MB sizes... LMFAO)... im joking on that one... well kinda... i want to try it bad but lack a system for testing... /cry
My System SpecsSystem Spec

 Is it possible to create a C: drive with 64K clusters?

Thread Tools

Similar help and support threads
Thread Forum
Bad clusters, Read failure, bad sectors
CHKDSK “Bad Clusters” and “Read failure” on C: drive: - My computer is a Windows 7 Home Premium 64 bit SP1 with 8GB RAM. The HDD has 93GB used space and 204GB of free space remaining. After reading the details see question at end. After failing to create an image of my C: drive...
Performance & Maintenance
bad clusters, read failure, bad sectors
CHKDSK “Bad Clusters” and “Read failure” on C: drive: - My computer is a Windows 7 Home Premium 64 bit SP1 with 8GB RAM. The HDD has 93GB used space and 204GB of free space remaining. After reading the details see question at end. After failing to create an image of my C: drive...
Performance & Maintenance
Backup failure; Bad clusters
I was creating a system image backup last night and it failed because of bad clusters. Now i have 11 DVDs that were part of that backup. Do I have to start all over again?
Backup and Restore
recovery of bad clusters - any log?
I believe one of my external hd has developed some bad clusters and they do appear on a surface scan. So I ran Windows 7's "automatically fix file system errors" and "Scan for and attempt recovery of bad sectors". Is there a way to find out what bad clusters Windows found and recovered without...
Performance & Maintenance
since sector size is based on powers of 2, and clusters can be one or more sectors. is my hdd programed in a non-most basic of programming languages since it has like 43 million + sectors and is a mere 240GB in size?
Hardware & Devices

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

© Designer Media Ltd

All times are GMT -5. The time now is 01:23.
Twitter Facebook Google+