G.SKILL F1-4000USU2-2GBHZ PC4000

G.SKILL F1-4000USU2-2GBHZ PC4000

Value and Conclusion »

Test Setup

Test System
CPU:AMD Athlon64 3200+ Winchester (multi lowered to 9)
Motherboard:DFI LanParty NF4 UT (Bios 623-3)
Memory:2x 1024 MB G.SKILL F1-4000USU2-2GBHZ PC4000
Video Card:MSI NX6600GT TDI128E
Harddisk:Hitachi T7k250 160GB
Power Supply:TSP 420W
Software:Windows XP SP2, Forceware 81.85 official

We will be testing this memory at 1T timing only, because that is what enthusiasts are using to get maximum performance out of their memory.

Alpha Timing settings in Bios:


First we tried to determine the fastest timings for 200 MHz at 2.6V, the result was 2.5-3-3-8. After this we increased the voltage and tried to lower the timings again - no go. So it is not possible to run CAS Latency 2 at 200 MHz - not the best result for 200 MHz.

Then, we tested how far we could overclock the memory at 2.6V with tightest timings possible. We reached 228 MHz. When using the more relaxed timings of 2.5-4-4-8, our overclock dropped four MHz down to 224 MHz, which is strange. We did not run any benchmarks at these setting, since the 228 MHz @ 2.5-3-3-8 will yield better performance in all cases.

Now we changed to 3-3-3-8 and got 242 MHz, then 263 MHz at 3-4-3-8. When running at the manufacturer's official specification of 3-4-4-8 we could overclock from 250 MHz to 275 MHz. That's a nice result for a 2 GB kit. Generally, 2 GB kits do not overclock as well as 1 GB kits.

Now we increased voltage in several steps to 2.8V, 3.1V and 3.3V. We saw absolutely no increase in maximum clock speeds.

The last test "JEDEC DDR-400A" is for comparison with a generic DDR module running at JEDEC standard timings.

G.SKILL F1-4000USU2-2GBHZ PC4000
CPU Clock &
Memory Ratio
Quake 3
Mod 1M
9 x 200 1:1200 MHz2.5-3-3-8 2.6V5789 MB/s2200 MB/s49.3 ns431.11855442.12 s
9 x 224 1:1 224 MHz2.5-4-4-8 2.6V------
9 x 228 1:1 228 MHz2.5-3-3-8 2.6V6445 MB/s2394 MB/s45.7 ns446.7 fps1903240.98 s
9 x 242 1:1 242 MHz3-3-3-8 2.6V6616 MB/s2445 MB/s44.6 ns468.4 fps1967138.24 s
9 x 250 1:1 250 MHz3-4-4-8 2.6V6951 MB/s2524 MB/s45.0 ns476.6 fps1970037.52 s
9 x 263 1:1 263 MHz3-4-3-8 2.6V7442 MB/s2649 MB/s44.1 ns503.1 fps2015535.52 s
9 x 275 1:1275 MHz3-4-4-8 2.6V7729 MB/s2790 MB/s40.6 ns520.9 fps2081733.75 s
JEDEC DDR-400A200 MHz2.5-3-3-8 2.6V5789 MB/s2200 MB/s49.3 ns431.1 fps1855442.12 s

If you are going to run this memory under the specification of 250 MHz, there might be better alternatives with tighter timings like G.SKILL's F1-3200BIU2-2GBHX. But if you want to overclock to high memory speeds, and need 2 GB of memory, you will love these modules.

SuperPi - 275 MHz; 3-4-4-8; 2.6V and SysTool Memory Timing screenshot


For easier comparison with other modules, we set the maximum voltage required for the best result (here 2.6V; max 3.1V) and tested until we found the highest clock frequency and fastest timings for this memory. The benchmarks Everest Read, Everest Write and Quake 3 were run. We then calculated the performance increase in percent compared to some standard DDR-400 memory running at JEDEC standard timings (2.5-3-3-8). The average percentage of the three benchmarks is listed in following table:

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