Is it normal for the MacBook Pro to make noises when I put it to sleep?

Question

I apologize for posting a new question so soon, but I wanted to get my technical problems with my MacBook Pro sorted out before I go back to school.
I'm worried about this one thing that happens when my MacBook Pro goes to sleep. After I close the laptop and it goes into "sleep mode" every few minutes or so it makes this noise like it keeps on turning on then going back to sleep, turning on then going back to sleep. It never did this before. Does anyone else hear these weird noises when it's in sleep mode?
For some reason it does not make these noises when I press the power button, and then press sleep. So this confuses me.

Answer 1

I have the same problem after just having my logic board replaced.
Here is what the log recorded....
9/27/10 9:57:58 PM kernel hibernate image path: /var/vm/sleepimage
9/27/10 9:57:58 PM kernel sizeof(IOHibernateImageHeader) == 512
9/27/10 9:57:58 PM kernel Opened file /var/vm/sleepimage, size 4294967296, partition base 0xc805000, maxio 400000
9/27/10 9:57:58 PM kernel hibernate image major 14, minor 2, blocksize 512, pollers 5
9/27/10 9:57:58 PM kernel hibernateallocpages flags 00000000, gobbling 0 pages
9/27/10 9:57:58 PM kernel AirPort: Link Down on en1. Reason 1 (Unspecified).
9/27/10 9:57:58 PM configd[14] network configuration changed.
9/27/10 9:58:00 PM kernel AppleYukon2: 00000000,47d12000 sky2 - HardwareNotResponding, marking offline
9/27/10 9:58:00 PM kernel System SafeSleep
9/27/10 9:58:00 PM kernel hibernatepage_listsetall start
9/27/10 9:58:00 PM kernel hibernatepage_listsetall time: 207 ms
9/27/10 9:58:00 PM kernel pages 562038, wire 91802, act 107548, inact 24, spec 90, zf 0, throt 0, could discard act 44110 inact 100896 purgeable 9962 spec 207606
9/27/10 9:58:00 PM kernel hibernatepage_listsetall found pageCount 199464
9/27/10 9:58:00 PM kernel IOHibernatePollerOpen, mlget_interruptsenabled 0
9/27/10 9:58:00 PM kernel IOHibernatePollerOpen(0)
9/27/10 9:58:00 PM kernel writing 197868 pages
9/27/10 9:58:00 PM kernel image1Size 247805952
9/27/10 9:58:00 PM kernel PMStats: Hibernate write took 15966 ms
9/27/10 9:58:00 PM kernel all time: 15966 ms, comp time: 1326 ms, deco time: 0 ms,
9/27/10 9:58:00 PM kernel image 507706368, uncompressed 810799104 (197949), compressed 500398848 (61%), sum1 2c0f7a54, sum2 8f089b96
9/27/10 9:58:00 PM kernel hibernatewriteimage done(0)
9/27/10 9:58:00 PM kernel sleep
9/27/10 10:01:55 PM SyncServer[479] [110f30] |SyncServer|Warning| Refreshing watchdog because of a calendar time change alert.
9/27/10 10:01:55 PM kernel Wake reason = EC LID0 FRWR
9/27/10 10:01:55 PM kernel System Wake
9/27/10 10:01:55 PM kernel Previous Sleep Cause: 0
9/27/10 10:01:58 PM kernel AirPort: Link Up on en1
9/27/10 10:01:58 PM kernel AirPort: RSN handshake complete on en1
9/27/10 10:01:58 PM configd[14] network configuration changed.
9/27/10 10:01:59 PM ntpd[26] bind() fd 25, family 30, port 123, scope 6, addr fe80::21e:52ff:fe76:1d0e, in6is_addrmulticast=0 flags=0x11 fails: Can't assign requested address
9/27/10 10:01:59 PM ntpd[26] unable to create socket on en1 (13) for fe80::21e:52ff:fe76:1d0e#123
9/27/10 10:02:11 PM ntpd[26] time reset +0.505758 s