Here's the log.
I 15:03:41 ImgBurn Version 2.5.0.0 started!
I 15:03:41 Microsoft Windows XP Media Center Edition (5.1, Build 2600 : Service Pack 3)
I 15:03:42 Total Physical Memory: 981,480 KB - Available: 573,452 KB
W 15:03:42 Drive D:\ (FAT32) does not support single files > 4 GB in size.
I 15:03:42 Initialising SPTI...
I 15:03:42 Searching for SCSI / ATAPI devices...
I 15:03:42 Found 1 DVD±RW/RAM!
I 15:03:56 Operation Started!
I 15:03:56 Source File: -==/\/[DISCOVERY IMAGE]\/\==-
I 15:03:56 Source File Sectors: 2,298,496 (MODE1/2048)
I 15:03:56 Source File Size: 4,707,319,808 bytes
I 15:03:56 Source File Volume Identifier: DISCOVERY_IMAGE
I 15:03:56 Source File File System(s): None
I 15:03:56 Destination Device: [0:0:0] ATAPI DVD A DH24AAS BP5N (E:) (ATA)
I 15:03:56 Destination Media Type: DVD-R (Disc ID: TYG02) (Speeds: 6x, 8x)
I 15:03:56 Destination Media Sectors: 2,298,496
I 15:03:56 Write Mode: DVD
I 15:03:56 Write Type: DAO
I 15:03:57 Write Speed: 6x
I 15:03:57 Link Size: Auto
I 15:03:57 Lock Volume: Yes
I 15:03:57 Test Mode: No
I 15:03:57 OPC: No
I 15:03:57 BURN-Proof: Enabled
I 15:03:58 Advanced Settings - Force HT: No, Online HT: No, OverSpeed: No, SmartBurn: Yes
I 15:03:58 Filling Buffer... (20 MB)
I 15:03:58 Writing LeadIn...
I 15:04:31 Writing Session 1 of 1... (1 Track, LBA: 0 - 2298495)
I 15:04:31 Writing Track 1 of 1... (MODE1/2048, LBA: 0 - 2298495)
I 15:13:51 Synchronising Cache...
I 15:14:09 Exporting Graph Data...
I 15:14:09 Graph Data File: C:\Documents and Settings\HP_Administrator\Application Data\ImgBurn\Graph Data Files\ATAPI_DVD_A_DH24AAS_BP5N_MONDAY-FEBRUARY-08-2010_3-03_PM_TYG02_6x.ibg
I 15:14:09 Export Successfully Completed!
I 15:14:09 Operation Successfully Completed! - Duration: 00:10:12
I 15:14:09 Average Write Rate: 8,223 KB/s (5.9x) - Maximum Write Rate: 8,661 KB/s (6.3x)
I 15:14:09 Cycling Tray before Verify...
W 15:14:16 Waiting for device to become ready...
I 15:14:32 Device Ready!
I 15:14:32 Operation Started!
I 15:14:32 Source Device: [0:0:0] ATAPI DVD A DH24AAS BP5N (E:) (ATA)
I 15:14:32 Source Media Type: DVD-R (Book Type: DVD-R) (Disc ID: TYG02) (Speeds: 6x, 8x)
I 15:14:32 Image File: -==/\/[DISCOVERY IMAGE]\/\==-
I 15:14:32 Image File Sectors: 2,298,496 (MODE1/2048)
I 15:14:32 Image File Size: 4,707,319,808 bytes
I 15:14:32 Image File Volume Identifier: DISCOVERY_IMAGE
I 15:14:32 Image File File System(s): None
I 15:14:32 Read Speed (Data/Audio): MAX / MAX
I 15:14:32 Verifying Session 1 of 1... (1 Track, LBA: 0 - 2298495)
I 15:14:32 Verifying Track 1 of 1... (MODE1/2048, LBA: 0 - 2298495)
I 15:19:30 Exporting Graph Data...
I 15:19:30 Graph Data File: C:\Documents and Settings\HP_Administrator\Application Data\ImgBurn\Graph Data Files\ATAPI_DVD_A_DH24AAS_BP5N_MONDAY-FEBRUARY-08-2010_3-03_PM_TYG02_6x.ibg
I 15:19:30 Export Successfully Completed!
I 15:19:30 Operation Successfully Completed! - Duration: 00:04:58
I 15:19:30 Average Verify Rate: 15,426 KB/s (11.1x) - Maximum Verify Rate: 22,445 KB/s (16.2x)
The main buffer was 100 the whole time. The device buffer dropped about 6 times but jumped back up immediately.